We'll good news and bad news. I am installing my new stereo and speakers. My old stereo worked fine but would cut out sometimes if the truck was running but would work fine if the engine. I removed it and plugged in the new head unit. Nothing happened and it wouldn't come on. I tried to plug in my old stereo and it wouldn't work either. I plugged the new stereo in in a friends truck and it immediately came on so it's definitely a problem my truck. Which wire to the stereo is the power on so I can put a voltmeter to it and trace it?? I really need my stereo working again. I also had the overhead lights on in the truck and I lost power to those to. They won't turn on. Could they be connected? I checked the fuse box under the column and the stereo fuse was still in tact

 

1990 Ford F350 Factory Radio Wiring Diagram

Car Radio Battery Constant 12v+ Wire: Green/Yellow
Car Radio Accessory Switched 12v+ Wire: Yellow/Black
Car Radio Ground Wire: Red or Black
Car Radio Illumination Wire: Blue/Red
Car Stereo Dimmer Wire: N/A
Car Stereo Antenna Trigger Wire: N/A
Car Stereo Amp Trigger Wire: N/A
Car Stereo Amplifier Location: N/A
Car Audio Front Speakers Size: N/A
Car Audio Front Speakers Location: N/A
Left Front Speaker Positive Wire (+): Orange/Green
Left Front Speaker Negative Wire (-): Black/White
Right Front Speaker Positive Wire (+): White/Green
Right Front Speaker Negative Wire (-): Black/White
Car Audio Rear Speakers Size: N/A
Car Audio Rear Speakers Location: N/A
Left Rear Speaker Positive Wire (+): Pink/Green
Left Rear Speaker Negative Wire (-): Pink/Blue
Right Rear Speaker Positive Wire (+): Pink/Blue
Right Rear Speaker Negative Wire (-): Green/Orange

Let me know if this helps.
Check grounds and fuses obviously.

 

Thank you. That's helpful. I tore it apart today and my multimeter says I have no power there. I used two different multimeters to confirm this. Beside the fuse box under the steering column access panel, are there fuses anywhere else? It got dark on me fast so I couldn't just trace the wire. Can i just run a wire directly to the accessory and constant wires with in line fuses?

 

You can do that, make SURE you put fuses in between. I used to wire all my stereos keyed and constant power from the stereo to the constant from the truck. You just have to make sure you shut the stereo off every time you get out.
That will get you going but you need to find out why there is no power to that circuit. You have checked for power have you dug around to check the grounds? My 97 has fuses under the dash and the hood.im not sure on yours.

 

it cracks me up whenever I go to a junkyard and I see how hacked up the dash and the fuse box always is in these trucks. My truck came with 5 switches drilled into the dash at various spots and none of them had wires on them when I bought the truck. I'm curious what the wires dead but I'll never know.

 

I'm really big into volkswagens and you would be amazed by some of the stuff I have seen on these poor cars especially the fiberglass dune buggies. I pulled a rats nest that could fill a trash can almost out of my poor car. Different engines lights blah blah blah .

 

I checked the ground and even ran a separate ground wire direct to the battery as a test and I still had no reading. .

Ya, it amazes me what people do to their vehicles. I once went to look at the truck I thought was gonna be my next project. I call the owner and he said "it runs good, just needs a tuneup and some of the lights were rewired. 1500 takes it home." I said do you mind if I look ut over before you drive here to make sure i like it? " he said that was fine and to call him back if I want to talk numbers. I look inside and find no foam on the driver seat and the radio was hacked out. It didn't get much better. The rest of the interior was pretty much shot. I open the hood to find a complete hackjob of the wiring. I pull out the dipstick to find TAR! I take off the air cleaner expecting to find a nasty filter. I take off the top and was greeted by a rat nest with a rat that jumped out. I put it back on and walked away. I expected very little at 1500 but that truck was SHOT

 

Sometimes, if you are doing a higher powered stereo, the best thing is to run a new circuit. I have a few aux circuits, so I got a 12 position fuse block from JC Whitney, and ran a length of 8 ga. wire directly from the battery (side of the starter solenoid) I also used this as an opportunity to replace a bunch of separate wires that had been run over the years, which really cleaned things up. Of course you will still need an "on" connection from the ignition, which you will have to likely pull off the standard fuse block, once you have isolated and eliminated the defunct wiring. (always a good idea). If somebody had the truck before you, I'd check anywhere you can think of to find other fuse blocks or inline fuse holders, people like to stick them in stupid places. BTW, my ext. fuse holder is on the firewall behind / above the brake pedal. It was a real pain to install, but it is ideally located reletave to basically all of the interior wiring, and you can check fuses standing outside.

 

I'm just putting in a head unit and replacing the front speakers with stock size ones. This truck had a Kenwood installed when it was new but it has gone far downhill since. So I doubt that it is from pulling too much power. I think I'm gonna just get a fuse block and run new wiring.

 

Frequently, door speakers are **** to deterioration from moisture that gets past the outer window weatherstrip that runs along the bottom of the side windows. The solution (at the beginning) is to get a pair of the foam speaker shields from Crutchfield, which also improves the sound by creating a baffle. I have a set in my Miata, and wish I had put them in my truck as well. (on the list) I don't think they are more than 15 bucks or so.

 

Check your fuse panel underneath the steering column.

One of the fuses probably needs replaced.

This happened to me when I installed my satellite radio through the third brake light. one of the contacts of the brake light hit a piece of metal and "pop" fuse blew.

There is some kind of grounding wire in the third brake light that controls the radio and illumination on the dash.

The fuse popped when I installed my cd player to.

No big deal. suppose to disconnect the battery when installing a radio though.

use a multi-meter set to continuity or a test light to test the fuses.

they make a kit that plugs into the back of the radio harness to fit a cd player. it only costs $5. I had to go to three different stores to finally find the harness. or you could order one from a parts store. I also had to get a radio antenna extension cable to reach my cd player.

take off the third brake light and make sure all three screws are making contact to the top of the cab, if its loose, that's a problem, because its integrated into the stereo and illumination on the dash,

 

As you can see in my first post I did that.


I'll replace the fuse anyway and see what happens. And thank you VERY much for the cab light help. I'll pull it off tomorrow and report back. Thanks!