Intermittent Stock Radio

[Pumper253]

Vehicle: 1992 XLT 4x4 w/ stock AM/FM/Casette radio.

Problem: stock radio has become intermittent.
When it decides to work, all is OK, except that if the headlights are turned ON, the radio shuts off; turn headlights OFF, radio comes back ON.

I'm leaning towards a bad ground in the harness. Any one have any other thoughts?

 

[Roadrunner777]

If it has DNR on the cassette door, you have the premium sound package with a separate amp. The amp has a separate power on lead. It would be interesting to know what your system voltage is with lights off and on. And, completely from left field, see what happens if you clean your battery connections. Just a hunch.

 

[Pumper253]

Haven't been able to get under the hood yet.

But, did find out that radio will work with headlights ON, if the dashboard lights are dimmed completely OFF. Turning the lights UP will suddenly turn the radio OFF. Can cycle it On/Off this way.

And YES it does have the Dolby symbol on it, so I consider it to be the Premium Sound System, the amplifier is in the back as it should be.

 

[FIND]

Your head unit is bad. If power to the illumination is killing your stereo, then it is unlikely it is something external to the head unit. You can add a ground to test it if you want, just go from the case to any good ground on the truck, if it still doesn't work, then replace the unit.