Help replacing stock head unit in '84 BII

[SR185]

I need some help with the power wires for the new head unit I am installing to (finally replace the stock am/fm cassette deck.

The dash as a plug with 3 wires that I'm trying to figure out. The stock unit plugged into these. One wire is yellow with black stripes, and it has power when the key it turned. The second wire is light blue with a red stripe: it doesn't seem to have power with or without the key on. The 3rd wire is orange, and it doesn't have power either.

The new harness says to connect it's yellow wire to the wire that has power when the key is on - I connected it to the existing yellow wire from the dash. The new harness has a red wire you are supposed to connect to constant power to keep the radio memory - I connected it to the light blue/red wire.

My new head unit will not power on. I have it's ground wire connected to the chassis. Any suggestions?

 

[Insanejughead]

First off, make sure to run a new section of black wire to a metal spot in the dash and secure it with an existing screw. I recommend using a 16# or bigger wire. None of the wires your describing are meant for a ground and the original radio, I'm sure, used a different way to ground than your new headunit (direct ground, instead of a wire).

(Edit: I just now seen that you DID say you had a good ground. Sorry about that. I'm just going to leave what I said up there)

The light blue/red wire should be your illumination wire. It'll only have power when your lights and dashlights are on. That'll probably hook up to the orange wire on your new headunit. I don't know what the orange wire in the dash was meant for. My '86 Thunderbird specifies that the orange/white wire is for the power antenna, but my car doesn't have a power antenna. So that orange/white wire isn't hooked up to anything.

As for the 12v+ constant wire... I would recommend that you do this. Get a 16# wire again (light colored or red, to help you know it's a powered wire) and run it from an empty fuse spot in the fuse block. I did this on my thunderbird because for some reason, my interior lights that were tied in with the radio kept blowing the fuze and I couldn't figure out why. So, I ran an extra wire (with a female spade lug) directly from the fuse to the radio. I haven't had a problem since, and I have a much easier time diagnosing dash problems from radio problems.

It's a good fix that I did, and it doesn't look jerry rigged to anyone. The best thing is, is that you don't need to take the entire dash out. You'll only need to unbolt the fuse block to insert that female spade lug from behind. Then run the wire from there, over the pedals, and to the radio hole.

 

[SR185]

I ended up powering it direct from the fuse block and it works fine.

 

[baxtej44]

I ended up powering it direct from the fuse block and it works fine.

i'm pretty sure that's looked down upon........

 

[Insanejughead]

As long as there's a fuse that's in between the radio and the incoming power line to the fuse box, it'll be fine.

That's what I did to mine.

 

[will1861]

I agree, this is a great and safe way to do it. Fused and ran correctly.