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double-a
i replaced all the fuses on the fuse block today, many looked quite sorry indeed. now, after doing so, the headlights do not rotate up or turn on, no fog lights, and no wipers either. on the front of the fuse panel, all fuses are good, and i think they're all in their correct places. on the backside, everything looks good. there is, however, a wire up under the dash, near the fuse panel but not connected to it, that is a single spade with four brown wires. does this go anywhere on the block? and if not, what would happen if it had touched something on the back of the fuse panel?

thanks for any help. i did consult the color wiring diagrams, they are little help to me unfortunately. i'm good mechanically, but not much of an electrician. i would very much like for my headlights to work!

~a
ejm
Multiple brown wires into one connector sounds like the grounds near the fuse box.

There should be a 6mm stud on the inside of left bracket that the fuse box mounts to. If it has broken off any good ground to the body will work just as well.
double-a
QUOTE(ejm @ Mar 14 2004, 03:59 AM)
Multiple brown wires into one connector sounds like the grounds near the fuse box.

There should be a 6mm stud on the inside of left bracket that the fuse box mounts to. If it has broken off any good ground to the body will work just as well.

i see that ground connector, and it's fine. these are a different set of four brown wires, with a rubber-coated spade connector on the end. it was floating around above the fuse block somewhere, so i wondered if it belonged plugged into the block. apparently it does not, and i fear that the wire came into contact with one or more of the open spades on the fuse block, causing something to go very bad. hence the sudden absence of my headlights, fog lights, etc. signals work ok, as do brake and dash lights. here are some pictures:
IPB Image
and the fuses are all good, but still no headlights, fog lights, wipers... could that brown wire have screwed something up?
IPB Image

thanks for any help,

~a
Dave_Darling
Unless someone's been hacking the wiring, brown is always ground. Try hooking that up to a good ground and see if your "missing" components work.

I don't think anything really awful would happen if that ground touched a "hot" source, but I'm not certain. You'd probably have to find out what components and circuits those are the grounds for...

--DD
ejm
Those brown wires go to terminal 31 on the emergency flasher switch
double-a
brown is always ground, that's good info. i haven't done any electrical hacking myself, and the only thing i can see that's been added is two leads from the radio. when fooling around with the wiring, i placed that four-brown wire on the open spade at position 3, thinking it just popped off of there somehow. the wires got really hot, and there was a rather interesting smell in the air. so did i fry something?
ejm
Once the smoke clears take another look at the 8th fuse from the left. I think it should be a 16 amp on a '74 and the fuse that's in there does not look like its seated correctly. I always put those fuses into place "backwards" and then spin them around, it keeps the metal strip from getting pushed out of place.
double-a
QUOTE(ejm @ Mar 14 2004, 08:31 AM)
Those brown wires go to terminal 31 on the emergency flasher switch

how right you are! that set of wires must have popped loose along the way. i put it back where it belongs and also replaced that 8 fuse with a 16.

still no headlights, fogs, wipers, or fresh air blower... so i'll bet i fried something while i was in there. but what? are those items that aren't working part of the same circuit?

i do know the headlight motors aren't bad. i used the manual headlight height adjuster on the back of the motor to jack it up a bit on each side. then i pulled the headlight switch out and then back in. both headlight buckets popped up to their full position, then back down again... just like they should. so is it a relay that got burned out?

signal, parking, hazard, interior and brake lights all work fine. i need to find out how to fix this, or i won't be able to drive at night, that could indeed be a problem.

~a
ejm
Did you disconnect the battery while doing this? The problem could be there....

There are four red wires that are tied to the positive battery terminal. Two of the four red wires run power up to the dash. One of them feeds the fuse box. Fuses 10,11 and 12 (last three on the right) should have power all the time. The other wire goes to the ignition switch and powers the ignition and some low current "key on" stuff.

Check that the wires are making good contact at the battery cable....
double-a
QUOTE(ejm @ Mar 14 2004, 03:39 PM)
Did you disconnect the battery while doing this? The problem could be there....

There are four red wires that are tied to the positive battery terminal. Two of the four red wires run power up to the dash. One of them feeds the fuse box. Fuses 10,11 and 12 (last three on the right) should have power all the time. The other wire goes to the ignition switch and powers the ignition and some low current "key on" stuff.

Check that the wires are making good contact at the battery cable....

er... no, i did not disconnect the battery. i guess i forgot.

all the wires you describe are present, and seem to be making a good contact there at the + terminal. i gave 'em a little abrasion just to be sure and put them back on the terminal. no change.

what purpose do the relays serve, and could i have fried one or more of them? thanks for your help thus far,

~a
SirAndy
QUOTE(double-a @ Mar 14 2004, 04:20 PM)
what purpose do the relays serve, and could i have fried one or more of them?

haynes manual, page 128 ...

Andy
94teener
Your ignition switch, Pin X, may be open when the ignition is on thus not routing power to Pin 15 on your Lights Switch or the electrical switch that plugs into the back of the ignition switch is defective or has come partly loose from the mechanical part of the switch. Either of these will cut out all those items you indicated are still not working.

Remove the 4 wire brown group from Pin 31 of the flasher relay, it don't go there. I don't know off hand where it goes but, if you are positive that all four wires are solid brown, they all go to ground some place. Find a solid ground and connect them to it. Pin 31 of the flasher relay is not a good enough ground.

Good luck with it,

Phil
ejm
The shiny square relay is the high/low beam relay, the other square one is the flasher. The round ones are (not in order) horn, fog lights and what is referred to as the "fresh air fan relay" but it has other functions. The round ones are easily swapped around if you think there's a problem with one of them.

As 94teener has said, another possibility is the ignition switch "X" contact has failed. This is what turns the lights and wiper off when the key is turned to the crank position. Check for loose wires on the back of the ignition switch but first try this. Turn the wipers on and slowly turn the key to the on position and then to where it cranks. Try it a few times pushing in and up and down on the switch. See if the wipers work with the switch in a certain spot.

I'd drop by with a test light if you closer.....
double-a
QUOTE(SirAndy @ Mar 14 2004, 04:35 PM)
haynes manual, page 128 ...

Andy

yeah, i saw that page. it's not real helpful, the image doesn't even look like my fuse box. i have three rounds, one square and one tall mad.gif
double-a
QUOTE(ejm @ Mar 14 2004, 05:26 PM)
The shiny square relay is the high/low beam relay, the other square one is the flasher. The round ones are (not in order) horn, fog lights and what is referred to as the "fresh air fan relay" but it has other functions. The round ones are easily swapped around if you think there's a problem with one of them.

As 94teener has said, another possibility is the ignition switch "X" contact has failed. This is what turns the lights and wiper off when the key is turned to the crank position. Check for loose wires on the back of the ignition switch but first try this. Turn the wipers on and slowly turn the key to the on position and then to where it cranks. Try it a few times pushing in and up and down on the switch. See if the wipers work with the switch in a certain spot.

sounds like good info, i'll take a stab at it. i may have fried all those relays, since everything you mention (horn, air fan, foglights) doesn't work. the ignition is something i'm afraid to dig into, not wanting to mess this up any further.

i tried what you suggested with the wipers, no dice. they didn't budge a millimeter.

~a
ejm
QUOTE(94teener @ Mar 14 2004, 04:57 PM)
Remove the 4 wire brown group from Pin 31 of the flasher relay, it don't go there. I don't know off hand where it goes but, if you are positive that all four wires are solid brown, they all go to ground some place. Find a solid ground and connect them to it. Pin 31 of the flasher relay is not a good enough ground.

Terminal 31 on the flasher switch (E3) is where the factory wiring diagram shows the four brown wires going to. The switch is not being used as a ground, one of those four wires continues to a good grounding point.
double-a
QUOTE(ejm @ Mar 14 2004, 05:55 PM)
QUOTE(94teener @ Mar 14 2004, 04:57 PM)
Remove the 4 wire brown group from Pin 31 of the flasher relay, it don't go there. I don't know off hand where it goes but, if you are positive that all four wires are solid brown, they all go to ground some place. Find a solid ground and connect them to it. Pin 31 of the flasher relay is not a good enough ground.

Terminal 31 on the flasher switch (E3) is where the factory wiring diagram shows the four brown wires going to. The switch is not being used as a ground, one of those four wires continues to a good grounding point.

i'll leave those wires at terminal 31 for now, since my real problems don't have anything to do with those wires really. i just wanna figure out if i burned out the relays or if there's something more sinister involved. everything started when i plugged those four wires (mistakenly) into the fuse box, thinking they came from there. a little heat and a little smoke told me that what i did was bad!

i wish i could understand that wiring diagram. it's pretty, and i can grasp little things here and there, but mostly it's a mystery. a mystery i want to solve however.

~a
94teener
You probably will not hurt anything by leaving the 4 brown wire group connected to pin 31 of the flasher relay but, the 74, USA, wiring diagram only shows ONE brown wire connected to the flasher relay. (Don't confuse the BR/YW wires on the drawing as connected to pin 31 of the flasher, they are not.)

Phil
double-a
update: got a new ignition switch installed, and everything that wasn't working (fog lights, wipers, blower, horn) is now working. yay!

the headlights however, are not playing nice. the motors move the little guys to their proper position, but no light. any ideas? i almost got this problem licked, thanks to those of you who suggested a bad ignition switch.

~a
94teener
You have no headlights because the pin 15 to pin 56 connection of the headlight switch is not being made when you pull the headlight switch to the on position. Looks most likely the culprit to me.

Phil
double-a
that's a good idea, except that i've tried two headlight switches, with the same result.

~a
double-a
problem solved. according to the electrical diagram, the headlights receive power through the dimmer relay, that silver relay box on the fuse panel. i pulled it off and pried the innards out (as someone here in another thread suggested). sure enough, there was some fried plastic inside and a broken contact. replaced it, and now everything works as it should.

as an aside, i replaced the relay with a new aftermarket box, a silver one. it says "made in ireland" on the side, which i found mildly amusing.

~a
J P Stein
Good job.
Poring over an electrical diagram is not my idea of fun, but when you have a mess like you had.........

Now, no more magic smoke laugh.gif
double-a
yeah, it wasn't fun, but mistakes always seem to teach me more than successes. and i'm learning a lot lately wink.gif thanks for your help, btw.

~a
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