Just replaced the radio in my 1994 toyota pickup with toyota oem unit after a theft.

Radio is from 92 camry and is identical to the original radio in the truck (Harness is for external amplifier).

Amplifier is from 98 4runner and has the correct connectors (or so it seems).

Radio works fine and illumination on dial is bright, until I turn on the headlights. Then unit still operates, but goes dark. I have no illumination on any buttons, but don't know if this is normal or not. Have printed out wiring diagrams for all units involved, and they all seem to be the same.

Tried radio borrowed from installer that doesn't use the amplifier, and the same thing occurs. Unit plays, but goes black when headlights are turned on.

Please help.

 

I have a radio in my mercury mountaineer that does the same thing, except if I turn on the headlights in the day time, the light in the radio goes so dim that it is hardly noticeable. I am wondering if this might be the same thing. Have you tried it at night to see if it lights up then with the headlights on?

 

do you have a wiring diag to identify the illumination wire that comes from either the interior dimmer switch, or the headlight switch? if you can identify that wire in the radio connector, put a test light on it and see what haps.

you should light the tester when you switch on the headlights. it may be dimmable, and you may need to turn it up.

if it's external, you need to trace the wire back to the switch for a short or a miswire. if the short is within the radio, cut the wire.

my 88 doesn't have those fancy options so i can't offer more than that. good luck!

 

dark? There supposed to dim when you turn the headlights on...for the reason that they do not cause distractions at night.