View Full Version : Chevy wiring help

08-25-2007, 06:24 PM
Hi there ,

I need to wire my buddies 1980 Chev 1/2 ton for a 7 pin wiring .The trailer is ready to go but where do I Wire in the truck end.I did a google and found where each color goes to the 7 pin truck end ,it is what I need to know is what wires do I cut in the truck.I need some help ASAP!!!!!!

08-25-2007, 09:04 PM
The 7 pin harness is for trailer brake equipment. The wires to the pins ( in no particular order you will need a wiring diagram of the 7 pin plug for placement of the wires) go like this . . .

The first 4 you can wire right at the back with the tail light harness,
1 - ground
2 - park lights
3 - left turn + brake
4 - right turn + brake

Next 2 will need to have wires to the frt . . .
5 - trailer brake control
6 - (optional, not needed to wired to tow) trailer battery charge wire

# 7 is an optional wire and would be wired at the back . . .
7 - back up lights

you will need a test light and start probing the wires in the tail light harness at the back of the truck to figure out which wire is which the other 1 wire that you need will run back up to the trailer brake controler in the cab.

08-25-2007, 11:41 PM
Do yourself a favour and buy a draw-tite or similar adapter that plugs into the existing harness to access the turns/brake and tail light circuits. Scotch-loks will only cause hassles down the road with corrosion. And you will also need 2 30amp circuit breakers, 1 for trailer battery charge circuit, 1 for elec brake circuit. If it's a camping trailer you're towing, it's a good idea to install a heavy relay (solenoid) to isolate the truck battery so it doesn't go dead.

Most trailers are wired to "code", not that there is one but most mechanics wire them the same. Found this online, just remember the pictures are the wire end of the connector, not the mating end.


08-26-2007, 01:14 PM
yup stay away frm scotchlocks and t-taps