milosz

I would normally have my dome light switch in the center position, which is "dome lights go on when door is open." But I noticed the other day after getting in and starting the car that the dome lights stayed on for their usual 15 seconds and then turned off but instead of being completely off all the interior lights are flickering at a dim level. All the lights flicker together at the same rate - the front dome lights and rear passenger lights are all dimly flashing randomly but all lights at the same time. So now I just have the interior lights set to "off" because they would continue to flicker when the car was turned off and I don't want to drain my battery (It's 6° F right now here in Chicago.... not a good time for any kind of battery drain.)

What could cause this? Is there a relay for the dome lights?

jpowersjr2

iTrader: (1)

Do you have LEDs for the dome lights? Mine do it (Diode Dynamics) and I just leave them in the off position.

slartibartfast

iTrader: (7)

Does the flickering stop when the interior heats up during your drive? I'm thinking the switch poles are so close together that contraction from cold could be causing intermittent contact. Had that happen with a brake switch after I adjusted the brake pedal height for better heel/toe.

milosz

They are LEDs. I've heard that they do this. It kind of makes sense to me; the circuit in the car's system that is turning the dome lights on when you open the door, then delays turn off for 15 seconds, is probably not a relay but some kind of semiconductor- a transistor that is turned on or off by the control system. There might be enough stray current trickling out of this "solid state relay" in the "OFF" state to cause the LEDs to illuminate a little. You'd never see anything if you had incandescent bulbs- the stray current is not enough to light them - but LEDs require FAR less power to emit light than a regular bulb.

I just noticed this, though it could have been going on for a while.

It is cold here in Chicago now - was minus 5° F last night. I think the cabin got up to about 65° F the other day when I was driving and first saw this. So, yeah, it seems to happen even when the cabin is reasonably warm.

milosz

The lights stopped doing this the other day when it was like 45° F outside when I checked. Then today, at 22° I checked and they are doing it again. Some kind of cold-weather effect...?

My car is trying to drain it's battery just when it's needed most.... hhahahaha