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79 underdash wire help

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Old Apr 28, 2019 | 11:55 PM
  #1  
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Default 79 underdash wire help

My first thread here.
I pulled a 79 out of the desert where it sat for 20 years and have been slowly rebuilding it over the past 16 months. It's originally an L48/automatic car with all interior options except rear defroster and CB).
Basically everything on the entire car has been rebuilt or replaced with new, just tying up loose ends to get it running reliably, then finish the interior and on to paint.
I have a few wires under the dash and along the console that I can't find a home for.
I have the classiccarwiring.com wiring diagram, which has been pretty helpful, until I got to this issue.
Any help will be appreciated.

This picture is of a black connector and black wire on the drivers side of the console that I am pointing to with the screwdriver.. Black should be a ground but I can't find the other end of the connector. Could this be "rear defog ground"? I don't
have that option.



This picture the green, green and purple wires with a black T connector. It's possible that it is for the neutral safety/reverse light sw but I can't find the other end of the connector.
They could also have something to do with the radio, which I don't have installed.

The other wire in this picture is the red connector with pink wire with black stripe. Granted there are a lot of pink wires on the wiring diagram but the only one that appears in this area of the console
is to the "defogger feed", (rear window defroster??) which, again, is an option I don't have.
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Old Apr 29, 2019 | 11:25 AM
  #2  
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The purple/green wires are for the clutch safety switch - which should remain unplugged, since you have an automatic (there is another similar connector attached to your atomatic shifter in the center console). I can't help you with the other wires.
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Old Apr 30, 2019 | 08:50 PM
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Default Mystery Wires

Originally Posted by jetplt67
My first thread here.
I pulled a 79 out of the desert where it sat for 20 years and have been slowly rebuilding it over the past 16 months. It's originally an L48/automatic car with all interior options except rear defroster and CB).
Basically everything on the entire car has been rebuilt or replaced with new, just tying up loose ends to get it running reliably, then finish the interior and on to paint.
I have a few wires under the dash and along the console that I can't find a home for.
I have the classiccarwiring.com wiring diagram, which has been pretty helpful, until I got to this issue.
Any help will be appreciated.

This picture is of a black connector and black wire on the drivers side of the console that I am pointing to with the screwdriver.. Black should be a ground but I can't find the other end of the connector. Could this be "rear defog ground"? I don't
have that option.



This picture the green, green and purple wires with a black T connector. It's possible that it is for the neutral safety/reverse light sw but I can't find the other end of the connector.
They could also have something to do with the radio, which I don't have installed.

The other wire in this picture is the red connector with pink wire with black stripe. Granted there are a lot of pink wires on the wiring diagram but the only one that appears in this area of the console
is to the "defogger feed", (rear window defroster??) which, again, is an option I don't have.
the three wires with black connector (dark green lite green and blue). Please tell me what they are for. I can’t find them on any schematic.
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Old Apr 30, 2019 | 08:52 PM
  #4  
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From: Blue springs mo.
Default Pink wire

I have the same pink wire that goes to ??????
whats it for???
radio power???
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Old May 1, 2019 | 09:45 PM
  #5  
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Originally Posted by bradleyb66
The purple/green wires are for the clutch safety switch - which should remain unplugged, since you have an automatic (there is another similar connector attached to your atomatic shifter in the center console). I can't help you with the other wires.
Thank you Bradleyb
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Old Jun 30, 2019 | 12:06 PM
  #6  
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I have the same issue with the three wire T shaped connector for the clutch safety switch.
I have a manual. Where does this plug in for a manual?

Thanks in advance.
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Old Jun 30, 2019 | 05:46 PM
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Originally Posted by andyanth
I have the same issue with the three wire T shaped connector for the clutch safety switch.
I have a manual. Where does this plug in for a manual?

Thanks in advance.
It plugs into a switch on the clutch pedal. Not sure about 79, but I think my 69 had a short (about 4") adapter wire that adapted the 3-wire T shaped plug to the connector on the switch.
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Old Jun 30, 2019 | 07:06 PM
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Originally Posted by John Vance
I have the same pink wire that goes to ??????
whats it for???
radio power???
That unusual plug and plain pink colour wire went into my fuse box in one of the extra spade connection for switched ignition power, it was for the power windows ,mine was a 1977 model.

Last edited by bazza77; Jun 30, 2019 at 07:09 PM.
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Old Jun 30, 2019 | 07:13 PM
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To the Original Poster , these wiring looms usually included all the necessary wires for all options , so if they weren't ordered then the connections were wrapped or just taped into the loom. Cheaper to just make one loom than to have to pay someone to remove sections .
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