Replacement LED Dome lights not working?

[jscherf92]

I have an 05 M&T and i recently replaced my dome lights with 9 bulb, LED lights. They have worked fine for over a month and suddenly this week they will not turn on. not when the doors open, not when i rotate the switch to on, or auto. I will be going in with a multimeter tomorrow, but i didnt know if anyone else had a similar problem, im not exactly qualified to inspect the inside of the switch itself.UPDATE:Did not get a reading off of either of the dome light fixtures, after testing the first, the front light (in the console with the sunroof switch) went out. I have also lost power to my radio, though the gauges still light up and my aftermarket LEDs and CB radio still have power.any thoughts at all would be most appreciated.

[star_deceiver]

Sounds like a blown relay or fuse.

[jscherf92]

alright, well i know what a blown fuse looks like, so i can check all of those, but how can i spot a blown relay? will it be obvious?

[star_deceiver]

Quote, originally posted by jscherf92 »But how can i spot a blown relay? Will it be obvious?Not too sure other then testing it.

[jscherf92]

alright thanks for the help. after checking every fuse in both boxes, running meter tests at all my bad points (and geting 00.0) i know there has to be something blown or disconnected, but i dont know what.

[joatmon]

The dome lights use a switched ground. Did you test the dome light terminals to a known ground (such as roof metal)?Doe the radio make sound bt just not light up? Do you get the flashing LED, or is it completely dead, no audio and no lights of any kind?Do your tail lights still work, does the dimmer switch affect the brightness of the gauge lights when the headlights are on?If you have power locks, do they still work?What circuit are the aftermarrket LEDs and CB radio connected to?

[jscherf92]

Alright now i feel like we could get somewhere. Here is what i know, feel free to ask more questions because i know the more info i can provide the better.- I have yet to test a known grown, but i will try it in the morning-The radio is completely off, so i pulled it out checked its fuse, which was fine, and tested the switched 12v and the constant 12v with the radio ground. the constant gave me a 12.0 reading and the switched was 0.0 so its the power connection.-the gauge lights stay a constant brightness, the dimmer switch doesnt control anything any more and i didnt get any reading from any combonation of its plug terminals-The power locks on the remote no longer work, i had to lock the car manually tonight.-And the electronics I wired are going through a 12v source that is under the center console, where an additional cig outlet COULD be housed, but is not. And all of my aftermarket components are fused individually, and they are all working fine.Thank you so much in advance and let me know if there is anything i need to do/buy/fix in the meantime.

[joatmon]

I know you checked the fuses, but ...If the underhood DOME fuse was bad, then you wouldn't get power to the dome lights or the light in the sunroof control (or the mirror if you didn't have a sunroof) You also would not get a door ajar light in the cluster when a door was opened. The DOME fuse also supplies power to the wireless door lock receiver. I'm not sure if the door locks (hitting the button on the door) will work with a bad DOME fuse.The DOME fuse gets it's power pretty much directly from the battery, so since anything works, it should be getting power. Can you pull the DOME fuse and use a voltmeter to see if one side of the fuse is getting 12V?The dimmer will only affect the instrument lighting brightness when the head lights (or running lights) are on, you didn;t say for sure, did you try that with the headlights on? The instrument lighting is tied to the TAIL fuse, be sure to turn the headlights on all the way manually and verify whether or not you have tail lights, at least sometime before you drive in the dark.edit - since the dome fuse was blown, the radio must have been getting switched power, but not the constant 12V, so the rest of this is N/AThe switched radio power comes from the CIG fuse, which also powers the CIG lighter (12V outlet in the dash), so normally I'd assume that outlet is out as well. However, the power in the center console comes from the P-Point fuse, pretty much independent of everything, gets its power from the 100A ALT fuse,except that between the center console and the P-Point fuse, there is a relay, and the power to switch that relay comes from the CIG fuse. So, if the center console is getting power, the CIG fuse must be switching the relay. The power from the CIG fuse goes to a junction box over the glove comparment, and from there it goes to the Cig lighter, the radio, and the P-Point relay (on the top of that junction box. If the PPoint relay is getting power from it but the radio is not, and the cig lighter ?, then what have you been doing to the cars wiring you haven't told us about? seriously though, that combination of things acting up is odd, with no particular logical common point.

[jscherf92]

Yeah, im quite confused myself. The thing is, that my sunroof controls still work (for now...) and the lock switch on the actual door still worked. Ill try what youve suggested and get back to you later today.New update: After checking the DOME fuse again, it was blown, must have been something i tried yesterday. So now my radio is working again. With the front dome/map light; it gets a 12v reading BEFORE the light switch, but not after. So i guess this means the switch is blown? And i pulled out the dome light fixture again, and took a reading off of the plug harness, they are getting 12v AND i was driving at night and tested that dimmer switch again, it does change the gauges brightness as it should, so it has to be something between the dimmer switch and the dome lights? ill be trying new bulbs as soon as i can find the ones i bought.Let me know what you think, and i really appreciate all your help.

[jscherf92]

Alright, so after a few more hours of plugging, testing and re-installing the fixtures, i have isolated the problem to blown bulbs. Now this wasnt the problem from the start, as i did not get a 12.0 reading on the light socket, but it is now the only problem. So ive ordered what i need and i thank you joatmon for all the help.

[A Psycho Martyr]

what a struggle! I'm glad this wan't happening to meI woulda overloaded this sites bad-word filter and shut it down.lol

[joatmon]

polarity matters on LEDs, so sorry of it's a dumb question, but now that you've got 12V to the fixtures, are you sure you have the bulb polarity right?