Dome light question

[RedD250]

Is there supposed to be a way to turn the dome light on when the doors are closed? I found the switch under the top of the dash that turns the little light on above the message center, but it does not turn on the dome light. Every other car I've had, you turn the headlight knob all the way to the right and the dome light comes on, but all that does is turn up the dash lights. The dome light comes on when I open the door. Thanks!

 

[brucejohnson]

First check fuses. In a fuzzy schematic (headlight switch)I found points to what appears to be a fuse 14. Another guess is a bad headlight switch. The dome light switch contacts in the headlight switch rheostat may be faulty.
Check your map/reading light. It should have three positions: one that puts 12vdc from the fuse box to illuminate the map light manually; one in the center to turn the map light off; and one to turn the map light on with the dome/interior light. So, slide to one side - slide to center - then slide to opposite side of the slide switch for the modes.

 

[RedD250]

Thanks, I'll check that if it ever stops raining.

 

[brucejohnson]

Thanks, I'll check that if it ever stops raining.

I have amended my post with some additional info regarding the map/reading light switch positions that may help troubleshooting the issue.

 

[RedD250]

That's odd, my map light switch only has 2 positions. slide it to the front to set the light to come on with the door open, and slide it back to turn the map light on with the door closed. I checked the fuse, and it's good (all of the fuses are good). My eyes aren't what they used to be, so unfortunately I am unable to see the writing on the 2 wiring diagrams that you posted. I should probably take the advice of others and get a FSM. Thank you for your help.

 

[brucejohnson]

That's odd, my map light switch only has 2 positions. slide it to the front to set the light to come on with the door open, and slide it back to turn the map light on with the door closed. I checked the fuse, and it's good (all of the fuses are good). My eyes aren't what they used to be, so unfortunately I am unable to see the writing on the 2 wiring diagrams that you posted. I should probably take the advice of others and get a FSM. Thank you for your help.

I understand the eyes being not like they used to be. I was having a difficult time myself. I prefer BIG sheets of paper to the puny digitized displays. (I'm feeling old now). The map/reading light switch is shown in the middle of the contacts so I assumed there were three choices. Baaad me... Once I found the second schematic, I realized Fuse 14(?) goes to the dimming circuit and wouldn't affect the dome lights. So far, I'd say the headlight switch is the most likely culprit, barring wiring issues. KISS Principle applied.

 

[RedD250]

So the headlight switch is indeed supposed to turn the dome light on when turned all the way to the right? If that's the case, it probably is the culprit. I can't even feel the detent at the end where it usually clicks into the "dome light" position. At least that's how it worked in my old GMC and Monte Carlo and Electra. Been years since I've driven anything this old haha.

 

[brucejohnson]

It should be the switch contacts in the headlight switch: Location B - 24 in the schematic.

 

[brucejohnson]

That's odd, my map light switch only has 2 positions. slide it to the front to set the light to come on with the door open, and slide it back to turn the map light on with the door closed.

And a third map/reading lamp operational mode would be with map light switch forward, doors closed and dome light switch (in the headlight switch) activated, the map/reading lamp comes on with the dome lights.

 

[RedD250]

Well, I feel like an idiot now... I just wasn't turning it hard enough. Nice solid click, and bam, dome light and map light on with the doors shut! Guess my switch is still in good shape. All the old cars I've had before, the "detent" wasn't really tight, just kind of bumped over. Amazing, 30 years old and everything still works except my power mirrors. Got to love these dead simple old trucks.

 

[brucejohnson]

That's great! Thanks for the follow-up. I guess there is something to the old adage "When all else fails, finesse, uh, beat it with a bigger hammer".
I'll head over to your power mirror thread and suggest an action.