I've got a 1998 F-150 extended cab that is having some trouble with the auxilliary lights. For some unknown reason, my interior dome light will not illuminate, and neither will the cargo bed lights. I can't get the dome light to come on no matter what I do. Opening the door won't do it, pushing the dimmer switch past the detent to turn it won doesn't work either. The bulb's filament appears completely intact. The fuse, which I believe is #8, is also not blown. The map lights on either side of the dome light work fine.

The cargo light also won't come on when the dimmer switch is pushed to the lights-on position. I haven't been able to inspect those bulbs yet, I plan on doing that tomorrow. I don't think it's the bulbs, since the done light looks okay. It's not the dimmer switch, because the dome light won't come on when the doors open either. Fuse is fine, unless I'm looking at the wrong fuse maybe? The only other thing I can think of is a break in the wiring which I really don't want to try and fix.

Help please! I'm getting tired of opening the door at night and not being able to see. Thanks.

SnubNose

 

Try fuse 14 in the interior fuse box, as well as the interior lamps relay which it the one all the way at the top of the fuse box, a small rectangular relay. The one under it is the battery saver relay which could also affect the courtesy lamp operation.

 

There's supposed to be a relay in position 1? Hmm, that might explain a few things...

Looks like I'm gonna have to buy a relay. Thanks, will try that and report back!

 

Did you just buy it and they never worked?

 

Yes, I bought it used and since I never test drove it during night I never noticed that it never came on. I went out today and bought the relay from a local Ford dealer and everything works now. Thanks for the tip!

SnubNose

 

For what its worth:
I replaced the door post switches and my dome light starting working in my Ford 76 f100 pickup. I got these from the dealer.