Intermittent electrical problem with "dome" light - 1987 300E
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1987 300e
Intermittent electrical problem with "dome" light - 1987 300E
So there's a switch position at the cabin light that "should" allow the cabin light to come on when one of the front doors is open. Setting the switch to other positions confirms that there are no blown bulbs, fuses, etc. - the lights come on/off as expected in all other switch positions.
BUT- when set to go on when you open a door, the light RARELY turns on. So far, I've not been able to correlate the light coming on with the car's position, uphill/downhill angle, etc. The switches in the doors appear to behave as expected: electrically open when doors are closed, electrically closed when doors are open.
You can pop any of the switches out and check for continuity with the spring-loaded button in or out; that's how I tested them.
Any ideas?!? This is most baffling...
BUT- when set to go on when you open a door, the light RARELY turns on. So far, I've not been able to correlate the light coming on with the car's position, uphill/downhill angle, etc. The switches in the doors appear to behave as expected: electrically open when doors are closed, electrically closed when doors are open.
You can pop any of the switches out and check for continuity with the spring-loaded button in or out; that's how I tested them.
Any ideas?!? This is most baffling...
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Joined: Jul 2009
Posts: 4
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230E w124
This is a baffling issue. It sounds like it could be a mechanical issue - i.e. something physical - as opposed to an electrical fault, given that you've found that the car's angular position affects the light.
You could try tracing the light cabling all the way from the light to the fuse box and then to the door switches, but I doubt you'd want to spend all that time.
You could try tracing the light cabling all the way from the light to the fuse box and then to the door switches, but I doubt you'd want to spend all that time.
