Dark brown/white wire
 

I have searched and searched the website and looked at the wiring diagram but I cannot find what this wire goes to. It comes out of the engine side bulkhead connector and is not hot, key on or off or accessory. Anybody know what it’s for? I have it tucked into the firewall gutter in the pic.

Re: Dark brown/white wire
 

Interesting. I just consulted my wiring diagram for V8 67-72 Chevy trucks and see no brown/white wire listed on the engine side bulkhead connector. The only brown/white I can find on the entire diagram originates at the key switch and runs to the bulkhead connector inside the cab but nothing on the engine side.

Hopefully someone will chime in here.

Re: Dark brown/white wire
 

My truck is a 1970 C/10 but this harness came from a 1972 C30, not sure if that matters or not.

Re: Dark brown/white wire
 

When does it get 12v?

Re: Dark brown/white wire
 

I checked it with the key on, key off, key turned to accessory, no voltage. I don't think there is power coming from the fuse block to this wire. The under dash harness is from a 1970 truck.

Re: Dark brown/white wire
 

try the headlamp switch

Re: Dark brown/white wire
 

My truck has one of these, as well as the TCS wiring, and they are not the same. Also, the TCS wiring does not get routed in the firewall gutter. Here's a thread that may help. I believe post #14 is correct...the pics in the last post are of the TCS wires and they are different than your pic. http://67-72chevytrucks.com/vboard/s....php?p=6919062