Dome light help

[Peripatetic]

I think I have the same quirk on my car. Does your car have one "plunger" on each side or two?

[durech]

I tend to look for the simple solutions first. You said you did not know if the PO had changed the interior lights to LEDs out not. First thing I would do is just pull one of the lights and look. If they are LEDs, then try removing dimmer relay. That should make if work (although you won't have any dimming effect)

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[Alan]

I think I have the same quirk on my car. Does your car have one "plunger" on each side or two?

I'm not 100% certain, but I think it's 2 plungers on the driver's side and one on the passenger side. I'll confirm later today and post my findings.

[81dmc]

There are two plungers on the driver's side and one on the passenger's side. One of the two on the drivers are for the buzzer, or in my case, the Cadillac door chime.

[Bitsyncmaster]

The use of diodes is to get logic circuits. The door logic needed was to have either door open to turn on the dome lights. The bad thing using diodes in a power circuit is you get a voltage drop of about 0.7 volts over each diode.

I've found the stock diodes can drop up to 1.0 volts so installing your own newer diode should keep that diode drop to 0.7 volts or less.

Now running the dome "timer" does reduce the dome light voltage drops so that is not important anymore in that circuit. The dome unit provides a parallel path for the dome ground current. If your running LEDs by just removing the dome "timer" your dome lights will only get about 10.5 volts.

[Alan]

There are two plungers on the driver's side and one on the passenger's side. One of the two on the drivers are for the buzzer, or in my case, the Cadillac door chime.

Yep. That's what I found, too.

How does the buzzer work? Key in ignition and door open? Car on and door open? I don't think mine works but I'd like to know how it should and why not. I do have 2 connectors on the switch that doesn't operate the door/dome lights.

[Peripatetic]

There are two plungers on the driver's side and one on the passenger's side. One of the two on the drivers are for the buzzer, or in my case, the Cadillac door chime.

Well my theory is out. I assumed that since my car was missing the plunger and the dome lights didn't work when the door opened that they were related.

I wonder what the buzzer sounds like.

[content22207_2]

The use of diodes is to get logic circuits. The door logic needed was to have either door open to turn on the dome lights.

Actually the purpose of the diodes was to turn on only the door edge lights on an open door (versus illuminating both door edge lights when only one door was open). Normal cars have door plungers only.

You can bypass the diodes and the dome lights will still work normally, ie: dome lights will come on if either door is opened. Of course bypassing the diodes means door edge lights on both doors will also come on if either door is opened -- not a problem if you've got good condition outer door seals and edge sweep weatherstripping (illuminated edge lights on the closed door won't be visible).

If you do bypass the diodes, either remove the dashboard door ajar bulb (incandescent) or replace it with an LED bulb (acts as a diode) to prevent the battery from draining backwards from the courtesy light circuit through the instrument cluster via the door ajar indicator.

CourtesyLightDiodeBypass.jpg

If you are running incandescent bulbs in the dome lights, bypassing the diodes will make them burn brighter.

Bill Robertson
#5939

[81dmc]

I wonder what the buzzer sounds like.

Best said by AdmiralSenn.

"dying goat being squeezed through a harmonica"