Printable Version of Topic

Click here to view this topic in its original format

914World.com _ 914World Garage _ Wiring Harness Question

Posted by: 76-914 Jul 14 2011, 09:47 AM

What do these go to. This car is a '73 which was originally a 1.7. I thought it was for the blower but it's not. It's the green and brown wires w/ the blue tape and comes off the small black harness that the coil wires come out of also.
Attached Image

Another shot showing the black harness from whence it comes.
Attached Image

Posted by: vsg914 Jul 14 2011, 10:00 AM

Did the car have ac? The brown would be ground. Got a better pic of the plug on the end of the green?

Posted by: StratPlayer Jul 14 2011, 10:08 AM

Thermotime switch??

Posted by: 76-914 Jul 14 2011, 10:10 AM

There is no physical evidence of a prior a/c install e.g. cut out in front trunk pan. I could take another pic but it is just a couple of fe spades crimp conn's.

Posted by: brant Jul 14 2011, 10:17 AM

did the 1.7 get replaced with a 2.0 motor out of a 1974/75/76 car?

I want to say it was 1974 (could be off a year) when they changed the blower wiring from the front T14 board pin, to the back T12 board pin

essentially they changed the fan blower motor from the chassis to the motor harness.

so it could be you just have a 2.0 motor harness from a 1975 or so motor in there.

brant

Posted by: Cap'n Krusty Jul 14 2011, 10:44 AM

Early cars ('70-'72) had the blower wires in the engine harness, and they were green and brown. That looks like what you have. Easy enough to take the cap off the engine harness plug and look where they go, or just use an ohm meter. Once you know which pins they go to, looking at a wiring diagram is gonna provide the answer.

The Cap'n

Posted by: SirAndy Jul 14 2011, 10:57 AM

QUOTE(Cap'n Krusty @ Jul 14 2011, 09:44 AM) *
Early cars ('70-'72) had the blower wires in the engine harness, and they were green and brown. That looks like what you have.

agree.gif

If you look at the relay board diagrams on the bird board, you can see the difference in the blower motor wire routing.

Early cars have it routed through the relay board to the rear connector and into the engine harness, later cars have it exit out the body harness just under relay board.

You have an early engine harness. If your main body harness is of a later date, be careful as the layout of the pins on the rear connector on the relay board changed somewhere in late '72 (if i recall correctly). You can use the early engine harness but i would double check all connections on the plug to the relay board to make sure they are on the correct pins.

bye1.gif

Posted by: 76-914 Jul 14 2011, 12:47 PM

QUOTE(Cap'n Krusty @ Jul 14 2011, 09:44 AM) *

Early cars ('70-'72) had the blower wires in the engine harness, and they were green and brown. That looks like what you have. Easy enough to take the cap off the engine harness plug and look where they go, or just use an ohm meter. Once you know which pins they go to, looking at a wiring diagram is gonna provide the answer.

The Cap'n

When I had the engine out I ohmed all the wiring and determined that this was the fan blower leads per the schematic and pin location on the relay board connector. However, when the install came I found the other two wires and thought WTF.gif And yes it is an engine from a 75-76 so it looks like I have duplicity, here. Yes? Any pit falls awaiting me?And thanks for the input everyone.

Posted by: SirAndy Jul 14 2011, 01:29 PM

QUOTE(76-914 @ Jul 14 2011, 11:47 AM) *
Any pit falls awaiting me?

You should disconnect the wires in the engine harness at the relay board plug and add the same jumper to the plug that all late model cars use.
That will power the wires under the relay board ...

popcorn[1].gif

Posted by: 76-914 Jul 14 2011, 04:04 PM

QUOTE(SirAndy @ Jul 14 2011, 12:29 PM) *

QUOTE(76-914 @ Jul 14 2011, 11:47 AM) *
Any pit falls awaiting me?

You should disconnect the wires in the engine harness at the relay board plug and add the same jumper to the plug that all late model cars use.
That will power the wires under the relay board ...

popcorn[1].gif

Not wanting to assume; the jumper would be the same two pins/poles that feed these 2 wires?

Posted by: SirAndy Jul 14 2011, 04:48 PM

QUOTE(76-914 @ Jul 14 2011, 03:04 PM) *
Not wanting to assume; the jumper would be the same two pins/poles that feed these 2 wires?

Quick search for:
+board +jumper

got me a nice list of threads about the topic at hand. shades.gif

Which also included this, showing the jumper on the rear connector:

IPB Image

Posted by: 76-914 Jul 14 2011, 05:03 PM

Thx Andy. I try to do searches but I think i put a space where one doesn't belong or vice verse. I usually end up with 2000+ results. I just don't get it with the search strings. Thx, again. kent

Posted by: Prospectfarms Jul 14 2011, 08:05 PM

I had to sort this problem out last month when tracking a short in my ignition harness. To make sure I understand the issue and ror future searchers I'll try to rephrase the information set out in this thread concerning power to the blower fan.

The blower on my '72 is powered by a green wire that originates from #11 at the 12 pin connecter at the regulator plate. the wires branch from that harness coincident with the supply wires to coil terminals #1 and 15.

1973-76 blower motor supply wires are from #11 on the 14 pin connector.

76-914 suspects that the mystery wires come from the 12 pin and are a "redundant" set of blower leads, since the blower is already connected -- presumably to a later model body harness -- at pin 11 of the 14 pin connector.

On 73-76 regulator boards, #11 on the 14-pin (body harness) connector shares continuity with #10 and #11 on the 12-pin (ignition harness) connector via a jumper. On 71 and 72 regulator boards there is no jumper. Sir Andy's suggestion is that since the blower is powered from #11 of the 14 pin, 76-914 should check to make sure the correct jumper wire is in place between the 12-pin and the 14-pin.

If I messed this up I hope someone will let me know.

Posted by: 76-914 Jul 14 2011, 09:55 PM

No, that is really great info. I just came in from tinkering with it. When I jumped 10 & 11 I used a very small jumper. Duh. I heard the fan motor dragging and saw smoke from the "small" jumper which couldn't handle the load. The plug doe not have pins in those 2 spots so I'm going to need 2 pins so I can make a jumper, I think. I say I think because I haven't jumped this with a large enough gage wire. So, those two wires with the blue tape would have plugged onto the coil if in an earlier version? They're certainly the right length to connect there as well.

Posted by: jcd914 Jul 15 2011, 02:24 AM

QUOTE(76-914 @ Jul 14 2011, 08:55 PM) *

so I'm going to need 2 pins so I can make a jumper, I think.

So, those two wires with the blue tape would have plugged onto the coil if in an earlier version?


You make a jumper wire out of the 2 extra blower wires in your engine harness. Pop the cover off the 12 pin connector and find the 2 extra wires pull enough of the green wire to cut it about 1 1/2 inch or so from the pin connector. Pull the brown wire out enough to heat the solder at the pin connector and remove the wire from the pin connector then solder the pin connector onto the short green wire you just cut. Now you have a 1" jumper you can bend into a "u" shape and put 1 end on pin 10 and the other on pin 11 and put the cap back on the connector. I would pull both wires out of the engine harness completely but you don't have to, just make sure they can't short to any hot wires.

The green wire would not have been connected to the coil, they would have plugged onto the blower motor mounted to the engine. The coil gets it's power from pin 7 on the 12 pin connector via a black/red or all black wire.

Jim

Posted by: 76-914 Jul 15 2011, 08:18 AM

I'll try that. Hopefully this morning if it doesn't go crazy, here. Thx, Jim.(and everyone else)

Posted by: SirAndy Jul 15 2011, 10:53 AM

QUOTE(76-914 @ Jul 14 2011, 08:55 PM) *
So, those two wires with the blue tape would have plugged onto the coil if in an earlier version? They're certainly the right length to connect there as well.

Say what? confused24.gif

They would have plugged into your blower motor. rolleyes.gif

Posted by: 76-914 Jul 15 2011, 02:53 PM

QUOTE(SirAndy @ Jul 15 2011, 09:53 AM) *

QUOTE(76-914 @ Jul 14 2011, 08:55 PM) *
So, those two wires with the blue tape would have plugged onto the coil if in an earlier version? They're certainly the right length to connect there as well.

Say what? confused24.gif

They would have plugged into your blower motor. rolleyes.gif

apparently i misread this

The blower on my '72 is powered by a green wire that originates from #11 at the 12 pin connecter at the regulator plate. the wires branch from that harness coincident with the supply wires to coil terminals #1 and 15.


Posted by: Prospectfarms Jul 16 2011, 06:32 AM


Sorry for confusing you. On the early harness the blower wires branch off from that harness at approx the same place as do the coil wires, eg, the blower and coil wires are "coincident" -- not the best use of that word, but i was using my telephone and trying to be terse. The error was mine.

QUOTE(76-914 @ Jul 15 2011, 04:53 PM) *

QUOTE(SirAndy @ Jul 15 2011, 09:53 AM) *

QUOTE(76-914 @ Jul 14 2011, 08:55 PM) *
So, those two wires with the blue tape would have plugged onto the coil if in an earlier version? They're certainly the right length to connect there as well.

Say what? confused24.gif

They would have plugged into your blower motor. rolleyes.gif

apparently i misread this

The blower on my '72 is powered by a green wire that originates from #11 at the 12 pin connecter at the regulator plate. the wires branch from that harness coincident with the supply wires to coil terminals #1 and 15.


Posted by: 76-914 Jul 16 2011, 11:15 AM

You won't hear me complaining about anyone offering their time or help. I just got around to shooting this pic ( I was dealing with clutch tube issues yesterday). As you mentioned above, both the 12 pin conn pic'd below and the 14 pin conn have the #11 hot green feed. Looking at the pic you can see that there is no pin in #10 space to use for a jumper and I believe the brwn lead is cut off in the harness somewhere as I cannot get continuity thru it nor can I find the other end of it. I do however have 12v at #10 on the board so if I acquire a pin and solder it in the #10 slot of the 12pin conn and kill the old conn's for the blower I should be good to go.

Attached Image

Powered by Invision Power Board (http://www.invisionboard.com)
© Invision Power Services (http://www.invisionpower.com)