Help identifying under dash connector

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Doubletop

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Can anyone advise what this connector is for? It’s under dash near steering column.

I have an 87 GMC with TH400 and someone did away with kickdown switch all together. So I’m trying to wire in a new one and found this connector under the dash but it’s spade terminals point a different direction than the kickdown switch I got.

Not sure if it’s the original switch connector or for something else all together.

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SquareRoot

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Looks like one of two connectors that go to the brake light switch. Some switches have two terminals, one for the lights and on to disengage the cruise control.
 

Doubletop

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Yeah, it's an identical connector, but there's one already connected there.
 

DanMcG

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What color are the wires?
 

DanMcG

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.
 

Doubletop

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One is pink w/black stripe and the other is purple
 

nvrenuf

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Do you have cruise control? See if the brake light switch has a second pair of terminals.
 

Doubletop

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I do have cruise control and I only see 2 plug-ins on the cruise control switch and they're both still connected.
 

Matt69olds

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One is pink w/black stripe and the other is purple


That sounds like the wiring for the torque converter clutch wiring. I know you said the trick has a 400 trans, did someone remove a 700 and swap in a 400?
 

Doubletop

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I don't think so, but don't know for sure.
 

Rickf

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If it's a 1500 with a 305, most likely came with a 700R4 and has been changed to a th400. What does the gear indicator have for letters?
 

Doubletop

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It has D, 2, 1. No overdrive on the indicator. It also has the kickdown relay on the firewall that appears to be original due to the harness. Does the relay come with the th400, 700r4, or both?
 

nvrenuf

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At some point, in pretty sure the th400 became the base model 3 spd auto for 3/4, 1 ton and vans so it’s possible it’s original but you don’t see many.
 

Edward Koleman

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Since the wire is pink/black and purple, that connector would be for the neutral safety switch for a clutch setup. I dont have my diagram in front of me to see where it connects for the auto trans, but that is what my 87 had before i did away with that circuit altogether. It is the same style connector as the brake light switches, except this one leads to the relay side of the starter motor. They probably cut it at the firewall or or the starter when they did the trans swap.
 

mtbadbob

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Since the wire is pink/black and purple, that connector would be for the neutral safety switch for a clutch setup. I dont have my diagram in front of me to see where it connects for the auto trans, but that is what my 87 had before i did away with that circuit altogether. It is the same style connector as the brake light switches, except this one leads to the relay side of the starter motor. They probably cut it at the firewall or or the starter when they did the trans swap.
His shift indicator is for a 3 speed. The HD V20's & 30's, were equiped with TH 400's, as my '87 is. You are probably right though, it's probably for a clutch set up.
 

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