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Help with wiring identification

GSTwithPSI

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I'm attempting to repair my hacked up wiring harness since the previous owner thought it would be a good idea to convert all the factory connectors to spade connectors. I'm in the process of connecting the factory connectors back to the harness but I'm having trouble identifying a few wires.

I'm working with the harness that contains the temp sensor connectors, and the O2 sensor plug. There are 6 wires total. I think I have identified all but the Blue wire with the black tracer. I don't know what this goes to, and I can't find it in any wiring diagrams. Can someone take a peak at their car and tell me what this wire goes to? When looking at the photo, just pay attention to everything before the crimp connectors (the actual factory wiring). I'm getting rid of the crimp connectors and soldering the factory plugs back in, so pay no attention to the wire colors after the crimp connector. The wire in question again is the blue wire with the black tracer, the 4th wire from the left as seen in the photo. If someone could shoot a pic of ALL the wires and what they go to that would help A LOT. Thanks in advancefor any help!
WP_000131.jpg
 

toybreaker

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Should be a single pin sender on the rear of a factory vr4 t-stat lower housing.

The orphan wire in question goes there.
 

DynastyLCD

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toybreaker, what is the purpose of that? when i had my GVR4, i left it attached, but i had an aftermarket temp sending unit instead of the factory temp gauge sending unit.
 

toybreaker

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I *believe* it's an additional/redundant safety for the a/c system.

If I remember correctly, grounding it will kick off the a/c compressor and turn on both fans.
 

GSTwithPSI

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Hey guys thanks for the help. Just to make sure, you are talking about the single tab sensor seen on the left side of the water neck in this pic correct?

Just so I have it right as seen in the pic below:
Top right sensor = Temperature sender to ECU
Bottom right = Temperature sender to dash gauge
Bottom Left = mysterious A/C sender (This is where the blue wire with the black tracer goes?)
WP_000133.jpg


Agfain, as seen in the pic below:
Top sensor = A/C thermo switch
Middle left side = EGR vacuum switch
(again) Bottom left sensor = Temperature sender to ECU
(again) Bottom right sensor= Temperature sender to dash gauge
WP_000056.jpg


I guess technically if that is what the mysterious blue/black wire is for, I don't really need in since the previous owner removed all the A/C components. All I really need in the temp sensor and the gauge sensors connected right? Can anyone tell me a reason why I need anything else but those two things since I don't have A/C on the car? Thanks for the help so far guys.
 

toybreaker

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WP_000133.jpg



Quote:

Just to make sure, you are talking about the single tab sensor seen on the left side of the water neck in this pic correct?




yes

It's worth noting that you can use this wire to command the fans to run at will using a toggle/rocker switch inside the car if you have deleted the a/c system.
 
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GSTwithPSI

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Ok can someone confirm the wire colors going to the following components:

Color of the two 2 wires going to the Top right sensor in this pic = Temperature sender to ECU
Color of the single wire going to the Bottom right sensor in this pic = Temperature sender to dash gauge
WP_000133.jpg


Here's the deal. I have 6 wires total.

2 Green w/ black tracer
2 Yellow w/ green tracer
1 Blue w/ black tracer
1 Green w/ red tracer
WP_000131.jpg


The only one I have definitely identified is the Blue w/ black tracer. Can someone give me a sure answer on the other 5? Also are the 2 sets of identical colored wires interchangeable (meaning the 2 Green w/ black tracer and the 2 Yellow w/ green tracer)? As it was hooked up by the last guy, the 1 Green w/ red tracer is going to the Coolant temp sender to the ECU. According to the diagram here (look at page 148) click, that is wrong, and it should not be hooked up there. Problem is, I can't find the 1 Green w/ red tracer anywhere in the schematic. Can someone take a look at their car and let me know what color wire goes where so I know indefinitely and don't have to redo this again? I wish I had another Galant to look at, as my 90 GST is totally different.
 

iceman69510

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This is what you need:

Single pin front (connector B01): Coolant temp gauge unit: Yellow/green tracer

T-pin front: Coolant temp sensor (connector B02): Green/black (crossbar of T) and yellow/green (stem of T position)

Single pin rear: Coolant temp for A/c (connector B-22-4): Blue/black

Two pin on top of housing: Temp for a/c cutout (connector B-22): Green/red (from wire side, round side up it is the right wire) and green/black

As noted, the green/red wire is for connector B22. That is shown on page 150 of the file you linked. The green/black should go to the ECU, and the green/red to the pressure switch and control unit.
 

GSTwithPSI

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Iceman thanks a bunch. Your post helped out a ton. For the life of me, I can't find connector B-01 anywhere on the diagram for the coolant temp gauge unit? Can you tell me what page you found it on and where it is in the schematic? And since I have 2 identical wires that are Green w/ black tracer and also 2 Yellow w/ green tracer, I guess I will have to find the corresponding pin out at the ECU for each wire and do a continuity test end to end in order to identify which wire is which. I don't really know any other way to decipher between the wires sharing the same colors. Do you have any easier ideas on a way to figure out which is which? Thanks again for your post iceman, it was very helpful.
 

iceman69510

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Quoting GSTwithPSI:
Iceman thanks a bunch. Your post helped out a ton. For the life of me, I can't find connector B-01 anywhere on the diagram for the coolant temp gauge unit? Can you tell me what page you found it on and where it is in the schematic? And since I have 2 identical wires that are Green w/ black tracer and also 2 Yellow w/ green tracer, I guess I will have to find the corresponding pin out at the ECU for each wire and do a continuity test end to end in order to identify which wire is which. I don't really know any other way to decipher between the wires sharing the same colors. Do you have any easier ideas on a way to figure out which is which? Thanks again for your post iceman, it was very helpful.



I think you may be ok with the duplicate wires as they appear to be grouped in your photo ('though I can't see the tracer colors in the photo...). On the right of your picture of the wires are two green together. Likely they go together for the B-22. Similarly on the left, with the yellow and green wires together. You could of course verify them with the ohmmeter.

I will look for the B-01 item.
 
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iceman69510

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B-01 is probably only in the meters and gauges circuit, which is 54-12, and not shown in the file you linked. I found it in the configuration diagrams that number the connectors. I drew up my own information for this area of the wiring and put it in my service manual since otherwise you have to search all over for it. You also basically have to repair this on every GVR4 because of heat aging.
 
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iceman69510

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Gotta be one in the how to section somewhere.
 

iceman69510

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TB, is that the black and white version for oldtimers?
 
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