I know this only my third post here, and second thread about the same issue, but I don't know what to do with it anymore.


I've had this truck a decent month or so now, and I've dealt with it's radio not working the whole time, and my boombox in the back seat doesn't get the best reception.

I bought it from my aunt who parked it after my uncle passed away about a year and a half ago, and I was told it worked when she parked the truck, and I have no reason to doubt her.

I've tried 3 different radios in this truck, the original tape-deck that it had, an Identical tape-deck from my Cummins, and an aftermarket CD player radio I had in my garage, none worked in it.

My next thought is that the wiring must be messed up, so I did some research and found the constant power wire, and ran a hot wire to the fuse panel, no luck. So then I try running a hot wire for the Key-on power, to the radio fuse in the fuse panel, no luck.
Later I found a little amber strobe light, like for a mail man or snow plow, and it needs 12 volts to work, so this becomes my "test light" and it lets me know that the constant power wire in the harness does have a constant 12 volts, interesting.
Then I try it on the key-on power wire in the harness, and sure enough it works too. So I decide to put everything back together in the hope that it might have just decided to start working, Nope, still dead.

The backlight comes on, and rarely the top bar of the third digit of the clock/station will light up, but rarely.


I don't get it. I really don't

 

Does it have a good ground?

 

Address the power issues first.

Radio should have constant power on Pink wire. (pin 7 of radio connector)

Switched power on Red w/White trace.

BOTH of those need to work for the radio to operate properly. if you are missing power on one or the other, find out WHY.

Constant power comes from Fuse 17 in the fuse block on side of dash.
Switched power goes thru fuse 7.

Make sure you have power TO those two fuses.

 

The ground is good, I Used it with my little amber strobe light.


It also shows me I have constant power coming through the pink wire in the harness, also that my hot fuse panel wire has 12 volts too.


The red/white key-on power wire in the harness does have 12 volts, when the key is on, like it should.
My hot wire has 12 volts when the key is on as well.


Basically, both power wires in the wiring harness are good, and my fuse panel wires are good too.


I know at least that the tape-deck from the one ton works, or it did a couple months ago.

 

Replace both fuses anyway. See what happens.

 

What fuses? I have the constant power hooked back up to in-dash harness, The key-on power is hooked into the radio fuse, replace it? it looked fine.
The I.O.D fuse?

 

Fuse 17, and fuse 7. Just as an experiment.....

 

Replaced Radio fuse, #7
Replaced I.O.D. fuse, #17


No change

 

Have you checked to make sure the radios you're using work in the one ton? We can spend a lot of time chasing electrical gremlins only to find that we started with a bad radio...

Basically, if you have a good 12v on the battery (pink) wire AT THE RADIO, and a good 12v on the switched/ignition wire (red/white) AT THE RADIO, and there nothing interfering with the ground, then I think it's got to be a bad radio.

Also, how are you checking the voltage? Are you using a multimeter? I've seen a crimped wire provide enough current to switch on a bulb, but not power what it needs to.

A few other resources for you:

http://www.the12volt.com/installbay/...etail/100.html

http://www.installdr.com/installdocs/dcp/PDF/327009.pdf

 

The Cummins needs speakers, but I do know that the CD player radio did work in it, but that was a couple of years ago.


I am just going on faith on the second tape deck radio, I haven't seen it work in person.




Now, when I hooked up the CD player radio, it would half-assedly light up, and it would start making a humming noise, from inside the radio, not the speakers. Key on, key off, didn't matter.


I have a multimeter, but I could spend weeks just trying to find it, But I did find a little amber plow light that needs 12 volts to work, so I used that as my test light.
put the ground on the radios ground wire, and touch the positive to whatever wire wanted to check for power.