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Broken Dome Lights
Posted: Thu Oct 02, 2014 5:01 pm
by rschrope
So I bought new dome light bulbs for both the front and back dome lights in my car. When I installed them, the dome lights still did not turn on. I checked the fuse box and the fuse isnt blown, and my overhead light still works fine. Is my problem definitely wiring? I don't know where to even start if I'm looking for a short in a wire somewhere? Please help
Re: Broken Dome Lights
Posted: Thu Oct 02, 2014 6:50 pm
by Derf
The dome lights can be shut off by the rotary wheel on the left of the dash next ot the instrument cluster (2003-2008). This wheel dims the instrument panel lights and also has a position to turn off the dome lights.
Re: Broken Dome Lights
Posted: Fri Oct 03, 2014 5:54 am
by ehoff121
Are they incandescent or LED?
If they are LED, polarity matters and you should try flipping around the bulb in the socket.
Are the dome lights the only lights not working?
Re: Broken Dome Lights
Posted: Mon Oct 06, 2014 4:41 pm
by rschrope
Ill check the light switch on my dash to make sure, and yes only the two dome lights arent working.
Re: Broken Dome Lights
Posted: Mon Oct 06, 2014 4:44 pm
by rschrope
The switch definitely isnt the problem
Re: Broken Dome Lights
Posted: Sat Oct 11, 2014 3:59 am
by joatmon
Dumb question I know, but having only had 03's with sunroofs, what year is this for, and what's the difference between dome and overhead lights?
Re: Broken Dome Lights
Posted: Sat Oct 11, 2014 5:27 am
by rschrope
Mine is an '03 with a sunroof, dome lights are the overhead lights in the car. One in the backseat one in the cargo area.
Re: Broken Dome Lights
Posted: Sun Oct 12, 2014 9:34 am
by Derf
The dome lights are run off the lighting control module (allows them to fade out after door is shut rather than shut off instant door is closed) The wiring I believe comes into two locations, front driver A pillar, (front pillar driver door attaches to, and I think the rear one is sourced in the bundle of wiring with he third brake light etc (can anyone verify?) If the fuses are good, bulbs checked, and no known secondary hardware issues (wiring, headliner smashed, water damage, mice etc) I would start checking the wiring going for signal to find the point of failure, either door activation (does the LCM know that the door is opened?), LCM failure (lighting control module) or rotary light switch on dash (even through you verified it was not off, these switches can fail leaving you without light). Below is a link that details tapping into the dome light circuit, this will give you a starting point with a volt meter to verify the issue. Will need some help with identifying wiring between the switch and lighting module to see if activation signal is.
Need to verify:
-Door open circuit, does the dash light up showing that a door is open, have you tried opening other doors/hatch to see if the domelight comes on. If the Dash does not show that any doors are open, the issue is in the door circuit and not dome light.
-Rotary wheel on dash, if not in off position, their is another position where it will turn dome lights on, does this work?
-LCM, either not seeing the doors opened, rotary light switch, or not sending output, could be "fried"
Link to some wiring detials, has video showing some wiring:
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Re: Broken Dome Lights
Posted: Sun Oct 12, 2014 4:05 pm
by rschrope
Door sensor is working, everything seems to be fine. I need to just start checking the wiring. If i read it correct it seems like the two wires to check are the red and white door panel wires to start. If it isnt there im not sure how to get further into the wiring?

Re: Broken Dome Lights
Posted: Mon Oct 13, 2014 1:45 am
by joatmon
Attached the matrix interior light schematic,which, for this circuit, is the same as the Vibe, in case it might help.
Under normal conditions, the dome lights get constant 12V from the dome fuse and the ground to turn them on comes from the dimmer switch. The dimmer switch can either provide this directly if the dimmer is in the "On" position, or from either the door switches or what Toyota calls the "integration Relay" if the dimmer is in the "Door" position. So even if the integration relay was toast, opening the door should still send a ground to the dome lights.
So when checking for the 12V supply, check it to a known good ground, such as the body sheet metal, and when checking for the switched ground signal, check for either volts to a known good 12V, or check for the difference between a short to ground and an open to ground, (which is different from 0 volts to ground)