Radio Wiring

[keegansquarebody]

Hello, I am installing a sound system in my 1987 Gmc High Sierra 1500. I am adding a line out convertor to the wiring instead of adding a new radio. There are two harnesses. One with a black, yellow, and gray wire then another harness with a gray and a gray with a peach stripe. Im wondering what wire i would attach the remote wire too.
Thanks,
Keegan

 

[Matt69olds]

Since these trucks never came with an amp or power antenna, GM didn’t include the wiring.

More than likely, you will either need to add the wire to the existing connector or use a port in the fuse box that’s powered only in the run or accessory position.

I’m assuming your radio plugs look like this?

If the radio is out of the dash, the wiring diagram is probably stamped in the case.

 

[keegansquarebody]

No it doesnt look like that. I only have 2 connectors. One is going to the one speaker in the dash which has two wires. The other has one black one yellow and one gray thats it

 

[Matt69olds]

Can you take a picture and share it here?

 

[WP29P4A]

A test light or Volt Ohm meter would let you know whats what and test for the different powers sources for. always hot, key on power and dash lights power. Verifying the 3 hots and the ground before you start hooking things up will save time trouble shooting later.

 

[CalSgt]

Just a guess based on typical GM wire colors:

Black - ground
Yellow - 12v ign. Switched power
Grey - illumination

I do agree with everyone’s advice to test them, definitely don’t trust my instincts.