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HalfMoon
I started my car tonight and noticed despite the headlight switch being fully in the off position, my dash lights are on and my license plate light is .
Odd. Never saw that before. Headlight switch I imagine....
Thoughts?
David
Addedum-and saw what I thought was a wisp of smoke come from under my dash at the windshield....perhaps my imagination?
dangrouche
Here is the bird board repair of the switch; I'd disconnect the battery, remove the switch and "smell it" to see if has shorted. If so, open it up and see what you got. otherwise, pull it and count the terminals and post a WTB. they are out there with club members for about $50

http://www.pelicanparts.com/techarticles/9...lamp_switch.htm
HalfMoon
QUOTE(dangrouche @ Jun 23 2014, 10:11 PM) *

Here is the bird board repair of the switch; I'd disconnect the battery, remove the switch and "smell it" to see if has shorted. If so, open it up and see what you got. otherwise, pull it and count the terminals and post a WTB. they are out there with club members for about $50

http://www.pelicanparts.com/techarticles/9...lamp_switch.htm


Thanks for the link!
D
HalfMoon
Hmmm....
odd question. Is the wiper switch and the headlight switch in bed with each other somehow? The high side of my wipers haven't worked for some time and recently the low side crapped out too. I got a brand new switch but no love.
I wonder if the two (possible light switch malfunction-power to wiper switch) are related?
That said, on 1973's, did they have a relay for the wiper? I don't think there was one....
Do chime in.
David

Addedum-I noticed they (the wipers) do try to take off every once and awhile, but they fail to operate fully.
Dave_Darling
The two switches do work with each other, in that at least part of the wiper switch is fed by the ignition switch.

The wipers use a relay in all (stock) 914s.

Dig out your favorite 914 wiring diagram and follow it along. You'll see how stuff is tied together.

--DD
HalfMoon
QUOTE(Dave_Darling @ Jun 25 2014, 05:54 PM) *

The two switches do work with each other, in that at least part of the wiper switch is fed by the ignition switch.

The wipers use a relay in all (stock) 914s.

Dig out your favorite 914 wiring diagram and follow it along. You'll see how stuff is tied together.

--DD


Thanks for that DD!
I assume it's one of the round ones behind the fuse box. I'll look at my diagram later on tonight.
And....the wiper switch is tied in to the ignition switch? or the headlight switch, or both (clarification)?
Again, thanks :-)
Dave_Darling
Wiring diagrams:

http://www.pelicanparts.com/914/914_electrical_diagrams.htm

73 wiring diagrams:
http://www.pelicanparts.com/914/parts/Elec...lectric_73A.jpg
http://www.pelicanparts.com/914/parts/Elec...lectric_73B.jpg
http://www.pelicanparts.com/914/parts/Elec...lectric_73D.jpg
http://www.pelicanparts.com/914/parts/Elec...lectric_73D.jpg

http://www.pelicanparts.com/914/parts/Elec...lectric_73E.jpg



Interesting. Part #26 is labeled "steering column switch", and appears to combine the functions of both the ignition switch and the wiper stalk.

The wiper motor gets power from the "fresh air relay", which is a power-supply relay for lots of stuff up in the dash.

I don't have time to check the other stuff on there. I'm not as fond of the 73 diagrams as the later ones, as I find them harder to read....

--DD
HalfMoon
QUOTE(Dave_Darling @ Jun 25 2014, 07:55 PM) *

Wiring diagrams:

http://www.pelicanparts.com/914/914_electrical_diagrams.htm

73 wiring diagrams:
http://www.pelicanparts.com/914/parts/Elec...lectric_73A.jpg
http://www.pelicanparts.com/914/parts/Elec...lectric_73B.jpg
http://www.pelicanparts.com/914/parts/Elec...lectric_73D.jpg
http://www.pelicanparts.com/914/parts/Elec...lectric_73D.jpg

http://www.pelicanparts.com/914/parts/Elec...lectric_73E.jpg



Interesting. Part #26 is labeled "steering column switch", and appears to combine the functions of both the ignition switch and the wiper stalk.

The wiper motor gets power from the "fresh air relay", which is a power-supply relay for lots of stuff up in the dash.

I don't have time to check the other stuff on there. I'm not as fond of the 73 diagrams as the later ones, as I find them harder to read....

--DD


I gathered that #26 is THE wiper stalk switch.
Venture a guess which relay is the wiper relay and fresh air relay (1973) from picture enclosed?
TY
D
Click to view attachment
HalfMoon
Interesting.
http://www.914world.com/bbs2/index.php?sho...p;#entry1903257
See reply two. Member reports there is NO relay for the wipers (unless an intermittent has been installed).
Or have I mis-read DD? Are you saying the fresh air supply relay serves as a relay to the wiper or does the wiper (non-intermitent) have a relay all by itself and if so, what's it's physical location?
Tanx
D
Addedum. Ah, yes, after carefully reading, it appears as if it gets it's power from the fresh air realy, that it does NOT have it's onw relay.
Reading is fundemental :-)
Begs the question, whe'res the physical location of the fresh air relay?
GeorgeRud
I may be way out there, but doesn't the light switch also dim the dash lights? If so, some of these switches have a position that turns on these lights ( I think when you turn the knob counterclockwise). I know I've had cars with that feature, just don't remember if the 914 had that feature.
HalfMoon
Ok. So I've fouund (in my manual of all place, lol) a diagram that tells me what the relay's at the back of the fuse panel are for, but I seem to recall 1973 as being different than all the other years :-(
The manual indicated the following:
A=Light dimmer
B=Fresh air fan (and horn, wiper, cig lighter as I recall)
C=Aux headlights (foglights)
D=Buzzer

Obviously the thing that's perplexing me is D=buzzer. As you can see from the picture of the back of my fuse panel, D is a round realy and not a buzzer. So, what the heck is it a relay for and does this anomally blow the validity of the other relay location/descriptions?
Readers want to know, lol.
Anyone got the skinny on 1973 (chime in Jeff!)
Thanks all
David
Click to view attachment
HalfMoon
QUOTE(GeorgeRud @ Jun 25 2014, 11:31 PM) *

I may be way out there, but doesn't the light switch also dim the dash lights? If so, some of these switches have a position that turns on these lights ( I think when you turn the knob counterclockwise). I know I've had cars with that feature, just don't remember if the 914 had that feature.


They do but that wouldn't explain why my rear tag light is coming on with the key in the "on" position. Also, as I recall the dash lights should only come on when the light switch is pulled halfway (parking lights) or all the way (headlights). The dash dimmer functionality of the headlight switch can be turned off (turned counterclockwise all the way past the detent) but only in the aforementioned positions. I believe they shouldn't come on at all when the switch is in the off position with key on.
Pretty sure it's either the fresh air relay and or the headlight switch as it's now appearing a multi functionality problem involving not only the dash/license plate lights coming on inappropriately but a failure of the wipers as well.
john77
I have a 73 that also came with mixed up relays. On mine the silver round one in the back is the buzzer relay (I believe it controls the open door warning buzzers??), the silver square relay is the headlight high/low beam and then the three black ones are for fogs, horn and the third, I think, is the power relay.

Check which one has a blue and white wire going into it and trace it back to fuse 1 (or vice versa trace one of the two blue/white wires from fuse one back to the relay - the other goes to the tach) that's the fog relay.

Whichever of the other two is connected to BOTH fuse 8 (red/white wire) and fuse 11 (red wire) is the horn relay.

Leaving you with the third black one that does... who knows smile.gif

OR an even quicker way to figure out which is which is to simply pull them one by one and see what's stopped working (I didn't have that luxury as the reason I was down there sniffing 40 year old dust in the first place was that my horn and fogs weren't working).

John



QUOTE(HalfMoon @ Jun 25 2014, 08:47 PM) *

Ok. So I've fouund (in my manual of all place, lol) a diagram that tells me what the relay's at the back of the fuse panel are for, but I seem to recall 1973 as being different than all the other years :-(
The manual indicated the following:
A=Light dimmer
B=Fresh air fan (and horn, wiper, cig lighter as I recall)
C=Aux headlights (foglights)
D=Buzzer

Obviously the thing that's perplexing me is D=buzzer. As you can see from the picture of the back of my fuse panel, D is a round realy and not a buzzer. So, what the heck is it a relay for and does this anomally blow the validity of the other relay location/descriptions?
Readers want to know, lol.
Anyone got the skinny on 1973 (chime in Jeff!)
Thanks all
David
Click to view attachment
ovilla
HalfMoon, I have the exact same issue as you and am currently waiting on delivery of a "new to me" switch. Anyway, I'm going to open up my old one (the later fat switch with extra terminal from my 75 2.0) and will let you know what I discover.

I've also been having an issue with my passenger light not coming up (but going down fine), so I think my switch finally melted on me. Also, right now, with the car on and volts at 12+, turning on my headlights makes my drivers side light go up and down continuously - as if it had a low voltage condition. My passenger side light still doesn't pop up on its on.
Dave_Darling
Sorry, I just noticed a typo! The third of the diagrams should be
http://www.pelicanparts.com/914/parts/Elec...lectric_73C.jpg

That's another page of actual diagrams, not just labels. It also shows most of the relays.

Hard to see some of the wire colors, but from seeing a bit of yellow on relay C I would say that is the horn relay (#51 in the diagram).

Part #54 is the "fresh air fan" relay, and the diagram shows red, black/red, red/white, and brown wires. That could match either B or D from your photo--again, the colors are a little hard to see, especially the tracers.

Anyway, match up the wire colors on the relay sockets with the diagrams and you should be able to see which relays are what.

--DD
HalfMoon
QUOTE(Dave_Darling @ Jun 26 2014, 10:45 AM) *

Sorry, I just noticed a typo! The third of the diagrams should be
http://www.pelicanparts.com/914/parts/Elec...lectric_73C.jpg

That's another page of actual diagrams, not just labels. It also shows most of the relays.

Hard to see some of the wire colors, but from seeing a bit of yellow on relay C I would say that is the horn relay (#51 in the diagram).

Part #54 is the "fresh air fan" relay, and the diagram shows red, black/red, red/white, and brown wires. That could match either B or D from your photo--again, the colors are a little hard to see, especially the tracers.

Anyway, match up the wire colors on the relay sockets with the diagrams and you should be able to see which relays are what.

--DD


Time to fess up. I was hoping for identification using the letters as I'm severly color blind (not joking). Mebbe I should take a less blurry image?
HalfMoon
QUOTE(john77 @ Jun 26 2014, 02:50 AM) *

...and then the three black ones are for fogs, horn and the third, I think, is the power relay...

Not sure if you meant left to right or right to left. Could you clarify using the letters in the image? That would be most useful as I'm quite color blind.
Thanx
D
HalfMoon
Somewhat academic at this point as I've repl;aced all three relay's with known good ones and I'm still encountering the same original problem.
But for the purposes of academia I was able to identify that B=horn (for sure), so C and D are still unidentified. One or the other is the fog light relay and one is fresh air fan relay.
Also notice the second image where I found yet another relay with which I have no idea it's purpose. It's not attached to the back of the fuse panel. It's just "under the dash". Says Hella, and that makes me wonder if it's a fog lamp relay. If so, then what the heck are C and D (in the image). Grrrr. Why the hell did Ma P make 73 odd?
Well as I said, it's a little academic at this point, identifying the relays...I've replaced all three round relays on the fuse panel back with known good ones. Relays weren't the problem anyway. I used a continuity tester on each slot of the fuse panel and discovered fuse eight was blown in a very subtle way (undetectable to visual unless you had it removed). So, I replaced the fuse with a 25 and as soon as the ignition key comes on the fuse blows.
So...what we have.
Dash lights and license plate lights coming on with headlight switch in the off position when the ignition key is in the on position. fuses blowing in slot eight with ignition key on. Wipers not working with old stock switch and new 924 switch (obviously due to slot eight blowing fuses). Now remember, in an earlier post I reported that I thought I had seen a wisp of smoke from under my dash....
At this point I think it's either a headlight switch (mines the fat one) or the ignition switch.
Thoughts, jibes and jokes?
Click to view attachment
HalfMoon
The mystery relay
Click to view attachment

Addedum-relay number 002479-01 is the turn signal/hazard flasher. Duh.
Dave_Darling
Much clearer pics, thanks!

D has a red, a red/white, a black/red, and a brown wire. That matches the wiring for the "fresh air" relay. (#54 on diagram part C)

C appears to have a white/yellow, a white/blue, a gray/red, and a red wire. If there is a black tracer on that red wire (could be), that matches the fog light relay wires. (#53 on diagram part A)

Now we know what the relays are.


Dash lights and license plate lights get their power from the main light switch. Find the black/blue wire plugged into the switch and unplug it. If the lights stay on, you are getting power from somewhere else. Very likely a power and ground connection swapped.

--DD
HalfMoon
QUOTE(Dave_Darling @ Jun 26 2014, 06:19 PM) *

Much clearer pics, thanks!

D has a red, a red/white, a black/red, and a brown wire. That matches the wiring for the "fresh air" relay. (#54 on diagram part C)

C appears to have a white/yellow, a white/blue, a gray/red, and a red wire. If there is a black tracer on that red wire (could be), that matches the fog light relay wires. (#53 on diagram part A)

Now we know what the relays are.


Dash lights and license plate lights get their power from the main light switch. Find the black/blue wire plugged into the switch and unplug it. If the lights stay on, you are getting power from somewhere else. Very likely a power and ground connection swapped.

--DD


I think I see three of em...
Click to view attachment
HalfMoon
Process of elimination.
I swapped in a spare (and known to be good) light switch and I'm still popping fuses at slot 8, with the same other symptoms happening.
Also, I think the wisp of smoke that I first reported was from the fuse when it originally popped.
Now I'm thinking ignition switch. Has anyone heard of slot 8 popping fuses due to a bad ignition switch?
As an aside, I didn't add or change wires in anything prior to this problem so somethings worn out as opposed to an operator error. And I suspect greatly it's a component as opposed to a wire short.
Thoughts, jokes, jibs?
D
Note-The addition of the 924 wiper switch occured AFTER the problem manifested itself.

Addedum-Hey...I wonder if the light dimmer could be at fault (marked as "A" in the image, Easier to eliminate than the ignition switch, that's for sure). I have a spare....
dadaDaveed
QUOTE(HalfMoon @ Jun 26 2014, 07:28 PM) *

QUOTE(Dave_Darling @ Jun 26 2014, 06:19 PM) *

Much clearer pics, thanks!

D has a red, a red/white, a black/red, and a brown wire. That matches the wiring for the "fresh air" relay. (#54 on diagram part C)

C appears to have a white/yellow, a white/blue, a gray/red, and a red wire. If there is a black tracer on that red wire (could be), that matches the fog light relay wires. (#53 on diagram part A)

Now we know what the relays are.


Dash lights and license plate lights get their power from the main light switch. Find the black/blue wire plugged into the switch and unplug it. If the lights stay on, you are getting power from somewhere else. Very likely a power and ground connection swapped.

--DD


I think I see three of em...
Click to view attachment



It's hard to tell where things are connected from this angle, but I'd double check the wiring of the headlight switch. It looks like the wires for terminal 58L and 15 might have been swapped. This thread should help.

http://www.914world.com/bbs2/index.php?showtopic=139356
JeffBowlsby
Here are some testing diagrams for the dash switches:

https://bowlsby.net/914/WiringHarnesses/DashSwitches.pdf

They can be found in the drawings section of my wiring harness website.
HalfMoon
QUOTE(dadaDaveed @ Jun 26 2014, 11:18 PM) *

QUOTE(HalfMoon @ Jun 26 2014, 07:28 PM) *

QUOTE(Dave_Darling @ Jun 26 2014, 06:19 PM) *

Much clearer pics, thanks!

D has a red, a red/white, a black/red, and a brown wire. That matches the wiring for the "fresh air" relay. (#54 on diagram part C)

C appears to have a white/yellow, a white/blue, a gray/red, and a red wire. If there is a black tracer on that red wire (could be), that matches the fog light relay wires. (#53 on diagram part A)

Now we know what the relays are.


Dash lights and license plate lights get their power from the main light switch. Find the black/blue wire plugged into the switch and unplug it. If the lights stay on, you are getting power from somewhere else. Very likely a power and ground connection swapped.

--DD


I think I see three of em...



It's hard to tell where things are connected from this angle, but I'd double check the wiring of the headlight switch. It looks like the wires for terminal 58L and 15 might have been swapped. This thread should help.

http://www.914world.com/bbs2/index.php?showtopic=139356


Interesting thread but his sole observation wasn't verified.
Also, I didn't swap em (the wires) and my system worked fine for quite some time.
Keep in mind that my car is a 1973 and the current (obviously PO replaced) switch is a later model "fat" switch, so the color ID's are different than the thread you so kindly posted.
Perplexed headbang.gif
HalfMoon
QUOTE(Jeff Bowlsby @ Jun 26 2014, 11:26 PM) *

Here are some testing diagrams for the dash switches:

https://bowlsby.net/914/WiringHarnesses/DashSwitches.pdf

They can be found in the drawings section of my wiring harness website.


Useful!
TY
D
HalfMoon
Today I thought I would pull the headlight dimmer switch and do a swap with another one I had and lo and behold I see my spare is quite different than what I have on my car. The one on my car has a "jumber" so I'm thinking the PO used a different dimmer and that this "jumper" is part of doing that. Notice in the image my spare has no jumper and the different number of tang contact points between the two.
Anyone have any experience with this?
I suspect my spare is the appropriate dimmer.
After this I can only think of one more component I can change before doing continuity checks on the wires and that would be my ignition switch (I do have a spare). Grrrrr.
How bout the difference of those dimmer switchs ya'll?
Click to view attachment
dadaDaveed
QUOTE(HalfMoon @ Jun 28 2014, 01:31 PM) *

Today I thought I would pull the headlight dimmer switch and do a swap with another one I had and lo and behold I see my spare is quite different than what I have on my car. The one on my car has a "jumber" so I'm thinking the PO used a different dimmer and that this "jumper" is part of doing that. Notice in the image my spare has no jumper and the different number of tang contact points between the two.
Anyone have any experience with this?
I suspect my spare is the appropriate dimmer.
After this I can only think of one more component I can change before doing continuity checks on the wires and that would be my ignition switch (I do have a spare). Grrrrr.
How bout the difference of those dimmer switchs ya'll?
Click to view attachment


Yes, your spare is appropriate for the '73. My car is a 73 also and I replaced a bad dimmer relay the same way (by adding the jumper). Just wire it the same way, with the jumper removed.
HalfMoon
QUOTE(dadaDaveed @ Jun 28 2014, 02:59 PM) *

QUOTE(HalfMoon @ Jun 28 2014, 01:31 PM) *

Today I thought I would pull the headlight dimmer switch and do a swap with another one I had and lo and behold I see my spare is quite different than what I have on my car. The one on my car has a "jumber" so I'm thinking the PO used a different dimmer and that this "jumper" is part of doing that. Notice in the image my spare has no jumper and the different number of tang contact points between the two.
Anyone have any experience with this?
I suspect my spare is the appropriate dimmer.
After this I can only think of one more component I can change before doing continuity checks on the wires and that would be my ignition switch (I do have a spare). Grrrrr.
How bout the difference of those dimmer switchs ya'll?


Yes, your spare is appropriate for the '73. My car is a 73 also and I replaced a bad dimmer relay the same way (by adding the jumper). Just wire it the same way, with the jumper removed.


Thanks DadaDaveed,
One thing that has me slightly confused....
Notice the difference in wire placement in comparrison?
My spare has the white wire at 56 and the yellow wire at 56a, but the one on the car (that's jumped) has the yellow wire at 56 and the white wire at 56a. Any thoughts about this?
Here's a better image and the schematic (Believe it's component 27 combination relay, right?):
Click to view attachment
Click to view attachment
Click to view attachment
dadaDaveed
I just pulled my fuse panel to take a look.

56 is where your Red is connected on both, as is mine.
56a is to the left and it should be White.
56b is to the right and should be yellow.
Yellow with red stripe goes to S
and if using a 5 post relay, a jumper should go from 56 to 30.
dadaDaveed
Honestly, I don't know if swapping 56a and 56b matters or not, but yours appears to be backwards from my functioning circuit. It's worth a try.
HalfMoon
QUOTE(dadaDaveed @ Jun 28 2014, 11:36 PM) *

Honestly, I don't know if swapping 56a and 56b matters or not, but yours appears to be backwards from my functioning circuit. It's worth a try.


One wonders if the PO wired em backwards and if this is the source of the problems originally posted?
I'm going to wire it the way it should be 56a white, 56b yellow.
Thanks dood!
D
HalfMoon
Made the dimmer switch tonight but no love. Fuses still blowing at 8, license plate lights and dash lights still coming on with headlight switch off ignition turned to on.
Next thing to try is swapping out ignition switches. After that, all I can think of would be doing continuity checks on wires to search for a broken one....
Unless you got a brainstorm?
Got one?
Poop.
Dave_Darling
Look for places (especially lights) where wires could have been switched around. Sometimes stuff like that will sort-of work for a while, and then something shifts a little and POP!

--DD
Tom
You need to find out why fuse #8 is blowing, According to the prints from Pelican, fuse #8 feeds the following: Fresh air blower and switch that controls the speeds, cigarette lighter, and wiper motor. With the power disconnected, use a multimeter to measure the ohmic value between ground and the load side of fuse #8. It should be very low, ( like 0 ohms - grounded), that is why the fuse is blowing. Now you need to see which wire is giving the low reading. If there are multiple spade terminals, remove them one at a time to find which one is grounded. One of them is bad, it is just a matter of finding the bad one and then fixing what is wrong.
Tom
EDIT: Quick check - pull the cig lighter out and see if there is corrosion inside. With lighter out does the reading on the load side of fuse #8 get higher in ohms?
Tom
HalfMoon
QUOTE(Tom @ Jun 30 2014, 08:31 AM) *

You need to find out why fuse #8 is blowing, According to the prints from Pelican, fuse #8 feeds the following: Fresh air blower and switch that controls the speeds, cigarette lighter, and wiper motor. With the power disconnected, use a multimeter to measure the ohmic value between ground and the load side of fuse #8. It should be very low, ( like 0 ohms - grounded), that is why the fuse is blowing. Now you need to see which wire is giving the low reading. If there are multiple spade terminals, remove them one at a time to find which one is grounded. One of them is bad, it is just a matter of finding the bad one and then fixing what is wrong.
Tom
EDIT: Quick check - pull the cig lighter out and see if there is corrosion inside. With lighter out does the reading on the load side of fuse #8 get higher in ohms?
Tom


Preliminary testing had the powered side of fuse slot eight at 1 ohm and the unpowered side at 0 ohm's. It didn't make a difference if the lighter was in or out.
Is that enough resistence to cause fault?
Tom
"0" ohms from the load side of the fuse to ground is bad. Since you mentioned about losing the wipers, I would look at that circuit. I don't remember if the connections on the load side of fuse #8 have multiple spade terminals or not. If so, remove one at a time and see if the resistance at fuse #8 increases. Don't worry about the powered side of fuse #8, just the load side that read "0" ohms. If in fact the load side has multiple terminals and one reads "0" ohms to ground, then try to identify where that wire goes to as it is causing a direct short to ground. That is why the larger fuse popped instantly. The lower the resistance, the greater the current. So that is too little resistance. If you have the time and desire, try searching for " Basic DC circuits". It will help you understand what you need to know to fix things on the car that involve electricity.
Tom
HalfMoon
QUOTE(Tom @ Jul 1 2014, 02:22 AM) *

"0" ohms from the load side of the fuse to ground is bad. Since you mentioned about losing the wipers, I would look at that circuit. I don't remember if the connections on the load side of fuse #8 have multiple spade terminals or not. If so, remove one at a time and see if the resistance at fuse #8 increases. Don't worry about the powered side of fuse #8, just the load side that read "0" ohms. If in fact the load side has multiple terminals and one reads "0" ohms to ground, then try to identify where that wire goes to as it is causing a direct short to ground. That is why the larger fuse popped instantly. The lower the resistance, the greater the current. So that is too little resistance. If you have the time and desire, try searching for " Basic DC circuits". It will help you understand what you need to know to fix things on the car that involve electricity.
Tom


Hey Tom,
I think I'm being a knob mebbe and screwing up terminology. When we say load side and powered side I think I'm misunderstanding so I'm going to use idiot terminology....
The side I referred to as the "powered side" and had a ohm reading of 1 (with the fuse out and the battery unhooked) lit up a test light when I had the fuse out and the battery hooked up, ignition key on.
The other side (which did NOT light up a test light when the fuse was out and the battery was hooked up, ignition key on) had a value of 0 ohm once the battery was unhooked. I think your reffering to this as the "load" side.
Load side and powered side are different?
Powered side lights up a test light=1 ohm (tested with battery unhooked)
Load side does not light up a test light=0 ohm (tested with battery unhooked)
Learning curve....
David
Note-I think I need to re-perform the tests with the battery unhooked and the ignition key on?
Addedum-I retested with the ignition key on and off, thinking this being a switched circuit when the battery is hooked up, but it made no difference in the values.
Tom
David,
The "load" side of a fuse is the side that feeds what ever electrical device, ie; " the load", that circuit is feeding. The "powered" side is the side that power from a power source is fed to.
In your case, the fuse is blowing. This indicates that the load is causing too much current to flow through the fuse, then it blows. So you do not need to take ohm readings on the powered side. Disconnecting the battery when working on electrical circuits is always a good idea. When you do hook the battery back up, don't tighten the bolt on the battery cable. Just push the battery cable back on tight enough to power up the car for testing. Then if something goes terribly wrong and the smoke starts coming out, you don't have to spend extra time untightening that battery cable bolt to remove power.
For fuse #8, try to divide the circuits on the load side to see which one is causing the ground.
Not saying finding the ground on the load side of fuse #8 will solve all of your problems, but these cars have some weird electrical issues from time to time and it wouldn't surprise me if it did. The circuits you are having issues with do have common connections, so it just may fix your lights issue also.
You don't need your key ON when doing these particular tests. Some tests may require that, but in your case with fuse #8 blowing, the key ON is not necessary.
Tom
HalfMoon
QUOTE(Tom @ Jul 1 2014, 01:37 PM) *

David,
The "load" side of a fuse is the side that feeds what ever electrical device, ie; " the load", that circuit is feeding. The "powered" side is the side that power from a power source is fed to.
In your case, the fuse is blowing. This indicates that the load is causing too much current to flow through the fuse, then it blows. So you do not need to take ohm readings on the powered side. Disconnecting the battery when working on electrical circuits is always a good idea. When you do hook the battery back up, don't tighten the bolt on the battery cable. Just push the battery cable back on tight enough to power up the car for testing. Then if something goes terribly wrong and the smoke starts coming out, you don't have to spend extra time untightening that battery cable bolt to remove power.
For fuse #8, try to divide the circuits on the load side to see which one is causing the ground.
Not saying finding the ground on the load side of fuse #8 will solve all of your problems, but these cars have some weird electrical issues from time to time and it wouldn't surprise me if it did. The circuits you are having issues with do have common connections, so it just may fix your lights issue also.
You don't need your key ON when doing these particular tests. Some tests may require that, but in your case with fuse #8 blowing, the key ON is not necessary.
Tom


Tom,
Thanks for the clarification.
I'm assuming I can check the circuits on the load side by detaching the particular wire from the back of the fuse block, connect my test lead to that wire, then trace the wire to the component detach that wire and connet my other lead to it, then take a reading?
Or, is it like how I tested the load side of fuse block 8? Which would mean I would detach the component wire from the back of the fuse block, connect my ohm meter, then merely connect the other lead from my ohm meter to ground and take a reading.
Having no real experience, this is all new to me. In the past, I've only used a continuity tester or a test light for simple testing (does it get power, can it get power)
Thanks once again for sharing your experience. My hope is that other members with no experience are following this and learning as well :-)
D
HalfMoon
Working on an assumption that each component wire from the load side of the back of fuse position 8 can be tested by probing each wire individually with a ohm meter and then connecting the ohm meter ground wire to a ground source would provide useable data, this is what I found.
Of those four wires all but one showed zero. The one (pictured) that had a value of 1 ohm appears to be red with a white stripe (I'm extrememly color blind, so this is a guess). Sadly the one right next to it also appears red with a white stripe....
On the schematic they appear to connect to component 63 Fresh air fan and component 30 Fan switch.
The other two wires go to 56 and 59 wiper motor and cigarette lighter respectively (and remember they are zero ohm).
My car is a v-8 converted, so I have neither fan or fan switch as both had been removed many years ago before I obtained the car. The current problems had not existed during my ownership rather they have just now occured (with the exception of the high side wiper not working despite ability to work when hotwired which has always been a thorn in my side).
I'm guessing that the wire with an indication of resistence is mebbe somewhere touching a ground source? Neither is actually hooked up to a component....so a broken wire or somehow grounding?
Or....that the other three wires showing zero are not supposed to show zero and I need to trace each one of those wires
All of the above are supisitions from a complete knob however and so could easily be wrong way Wilson.
See the photo and say something :-)
Click to view attachment
Tom
David,
First of all, you need to separate all of the wires from each other. Then take ohm readings between each wire to ground. The one or ones with the "0" readings will be the bad ones.
If someone previously cut and modified the wiring, it will be difficult for me to lead you thru what might be the problem as the wiring is no longer what the wiring diagrams show. However, I can lead you thru to find out why fuse #8 is showing "0" ohms. This will be done by making sure all of the wires from the load side of fuse #8 are separated and reading each to ground, then following that wire to where it is grounding and repair it. Don't despair because you don't understand electricity as well as others, I will walk you thru to the finish.
From your observations, I would suggest that the wiper motor or circuit is to blame.
A short explanation of DC circuits: The more resistance = less current and the fuse will not blow if within specs. The less resistance = more current and the fuse will probably blow. So if you have a reading of 2-3 ohms with a circuit that is protected by an 8 amp fuse, the fuse will not blow. Less than 1.5 ohms and the current will exceed 8 amps and the fuse will blow.
Hope this helps, if not, PM me and I will try to explain it better.
Tom
HalfMoon
QUOTE(Tom @ Jul 1 2014, 08:19 PM) *

David,
First of all, you need to separate all of the wires from each other. Then take ohm readings between each wire to ground. The one or ones with the "0" readings will be the bad ones.
If someone previously cut and modified the wiring, it will be difficult for me to lead you thru what might be the problem as the wiring is no longer what the wiring diagrams show. However, I can lead you thru to find out why fuse #8 is showing "0" ohms. This will be done by making sure all of the wires from the load side of fuse #8 are separated and reading each to ground, then following that wire to where it is grounding and repair it. Don't despair because you don't understand electricity as well as others, I will walk you thru to the finish.
From your observations, I would suggest that the wiper motor or circuit is to blame.
A short explanation of DC circuits: The more resistance = less current and the fuse will not blow if within specs. The less resistance = more current and the fuse will probably blow. So if you have a reading of 2-3 ohms with a circuit that is protected by an 8 amp fuse, the fuse will not blow. Less than 1.5 ohms and the current will exceed 8 amps and the fuse will blow.
Hope this helps, if not, PM me and I will try to explain it better.
Tom

Extremely helpful Tom and informative. I am learning!
I suspect I'll find something wrong with one of the red/black wires leading to 56 wiper. The wiper motor itself can be powered both high and low when hotwired (addedum-months ago when addressing another issue). We shall see tomorrow when I get further testing done.
I'm very grateful for your help and judging by how many looked at this thread others are gaining valuable information as well
D
HalfMoon
Did more testing today per Tom's recommendations.
Here's the results

Rd/wht Fan switch=1. ohm (not hooked up to a fan)
Rd/wht Fan=1. ohm (no fan installed)
Rd/blk lighter=1. ohm (with lighter in or out)
Rd/blk wiper= 0. ohm

Additional-
continuity test wire rd/blk from fuse block 8 to component 56 wiper= good
Hot wire component 56 wiper, pin 53a=fail
Conclusion=wiper motor bad or not grounded?

What say you Tom?
Tom
Sounds like a bad wiper motor to me. A good one should read from power input to ground of at least 1.7 ohms or greater, like 2.0 ohms or more. 1.7 ohms with 12 volts = just about 7 amps. where 2.0 ohms drops the amperage to 6.0. Too much less than that and your 8 amp fuse will blow. When it is "0" ohms, well the amps go thru the roof! Blown fuse, burned wires, etc.
If you disconnect the bad wire from fuse #8 and power up the circuit, does the 8 amp fuse blow? It shouldn't!
Tom
HalfMoon
QUOTE(Tom @ Jul 2 2014, 10:36 PM) *

Sounds like a bad wiper motor to me. A good one should read from power input to ground of at least 1.7 ohms or greater, like 2.0 ohms or more. 1.7 ohms with 12 volts = just about 7 amps. where 2.0 ohms drops the amperage to 6.0. Too much less than that and your 8 amp fuse will blow. When it is "0" ohms, well the amps go thru the roof! Blown fuse, burned wires, etc.
If you disconnect the bad wire from fuse #8 and power up the circuit, does the 8 amp fuse blow? It shouldn't!
Tom


Got out to the garage for a few minutes to do some testing.
My current wiper motor at pin 53a reads zero ohm, so I reckon the wiper motor is in fact bad.

My spare wiper motor reads the following
53a=1.900 ohm (power, right?)
53b=.500 ohm
31b=1.100 ohm
53=.340 ohm
Yet (with the spare motor properly grounded) and 53a hotwired-no function :-(

I've yet to soldier back together the other wires (sans the wiper motor wire) to the spade and reconnect to fuse block slot eight and power up with a fuse to see if the fuse holds. I'm sure it will.
Too hot outside for contunued testing, lol.
More testing later when it's cooled off a lil.
HalfMoon
Interesting afternoon out in the garage with Little Bastard.

Tom, you were right! I soldiered all the wires back together (except the rd/wht wire to the wiper), put a fuse in, powered the circuit up, and yes indeed it held! So, spade 53a having a zero ohm reading was blowing the fuse. I then soldiered the red/wht wire for the wiper back onto the spade for fuse slot 8, attached it to fuse block 8, detached the lead at the wiper for 53a, and predictably the fuse held.
But here’s where it starts getting weird…
With 53a unhooked, now my wipers (low speed) are working but only when the stalk switch on the steering wheel is in the off position. The other three positions don’t work (with the exception of shutting off the wipers. I might add the auto park function isn’t working either).

Originally a few weeks ago when my wiper system went south I assumed it also had something to do with the dash lights and license plate lights being on when the key was in the on position with the light switch in the off position, but I now feel the issues are separate.
The lights issue may be related to some mods I did quite some time ago to address the PO having put in an aftermarket tach. See this thread http://www.914world.com/bbs2/index.php?sho...218076&st=0 most notably posts 21 and 22. Could very well be I missed something and that’s what is responsible for the dash lights and license plate lights coming on inappropriately. The far greater issue has become the wipers, so the lights issue battle for another day.

The wiper issue I think is quite separate. So, as I was saying, a few weeks ago when I starting addressing these problems witch I thought might be related, one of the things I did was replace the stalk wiper switch with a 924 switch (as I also wanted to power an electric wash pump I’ve installed) and it’s possible the current switching issue has something to do with that
(see this thread http://www.pelicanparts.com/techarticles/9...tric_washer.htm and this thread http://www.914world.com/bbs2/index.php?sho...117014&st=0 most notably post 22 and 24).
I’m not at all convinced using a 924 switch is simply plug and play as it appears as if the wires may be routed differently at the switch than 914’s according to my switching symptoms. Pretty sure the wires at the wiper are correct but I may wrong. PO might have done some stuff and I’m color blind so I’ll take a picture and enclose it below.
Compounding the issue, last year I put a used wiper motor in addressing never having had a high side function and may have very well put in an earlier motor which I understand can quirk up things. See this thread http://www.914world.com/bbs2/index.php?sho...c=72503&hl=
That said, when I did swap out last year I had a low side wiper for quite some time (with a stock switch) but lost all functionality just recently the new 924 switch obviously not remedying the problem.

To be sure spade 53a at the installed wiper is causing fault and blowing the fuses. I didn’t test any of the other terminals hotwired on either the currently installed wiper or the spare, so I don’t even know witch spades powers the high side or the low side of those motors (which would be interesting to make further tests on).
53a showing zero ohm is definitely not gonna work so the motor has to come out for sure.
Do you happen to know which spades control which function Tom? That would be valuable for testing the spare and additional testing of the current installed motor. I may ,upon removal of the current motor, take a crack at opening it and seeing if it can be repaired (surely true if my spare and the previously noted test results show the spare as bad)

About as clear as mud, huh?
Having fun now aren’t we?
D
Click to view attachment
Tom
David,
Glad to see you now know what the problem with fuse #8 is. Reading thru the last thread makes me come to a possible conclusion that your original wiper switch may not be bad after all. Your wiper motor could have been the culprit all along. I don't know if a 924 switch will work properly or not. Maybe someone will let you know.
Is there someone local that you could have test their wiper motor for readings? I don't like the ones you posted for the spare. I will look at mine tomorrow to see if I can get some readings, however mine is a 76.
I will take a look at your other threads and see if something jumps out at me.
By the way, I am red/green color blind, so we are the blind leading the blind. LOL!! I have my wife tell me what color the wires are. smile.gif
Later,
Tom
HalfMoon
QUOTE(Tom @ Jul 4 2014, 02:28 AM) *

David,
Glad to see you now know what the problem with fuse #8 is. Reading thru the last thread makes me come to a possible conclusion that your original wiper switch may not be bad after all. Your wiper motor could have been the culprit all along. I don't know if a 924 switch will work properly or not. Maybe someone will let you know.
Is there someone local that you could have test their wiper motor for readings? I don't like the ones you posted for the spare. I will look at mine tomorrow to see if I can get some readings, however mine is a 76.
I will take a look at your other threads and see if something jumps out at me.
By the way, I am red/green color blind, so we are the blind leading the blind. LOL!! I have my wife tell me what color the wires are. smile.gif
Later,
Tom


I hotwire tested my spare and both high and low work! A lil worried about 53a with 1.9 ohm....
Might as well hook it to the cars harness and see what happens, right?
Tom
Remember that 53a goes to both your wiper motor and the fresh air blower. 1.9 ohms seems an OK reading to me. If the spare that tested OK on the bench does not work in the car, I would investigate that wiper switch.
Tom
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