No high beams and reverse lights '98 C280
 

I've been chasing down some electrical issues since I purchased this car recently. As the title says, no high beams from the stalk, both flash and regular setting ... and both reverse lamps don't light (bulbs are ok). I've checked all of the associated fuses but they're good. The blue high beam cluster light doesn't come on when key turned to 2.

I'm having some other convenience lighting issues -- lights blink when remotely locked, but not when unlocked, and the interior lights come on when unlocked but don't turn off after door closed --- somewhat annoying but I'll leave those for another day.

Any help is greatly appreciated! TIA :cool:

If the lights stay on after the door is closed you will have a dead battery another day... I wonder if the blinking on unlock is configurable? Is this a flood car? There are lots out there.

Do you get power (12V) to the high beam fuses when the lights are supposed to be on?
IF not then the combination switch is most likely the problem.

DOC, yes, I'm getting 12v at fuses 33/34 (L/R high beams) so I guess that rules out the combo switch .. could it be possible both high's are burnt out?

mpolli: I've turned off the interior lights for now and it is not a flood car AFAIK

Well that's a lot of different things wrong. I assume the reverse lights are controlled by the trans. And I can guess the high beams are controlled by a relay. The no blink on unlock is kind of strange as is the lights not turning off. The headlights are easy to access so you can check those. Do you get a bulb out indicator? I think you should on the high beams but I am not positive. You will probably just have to chase these down one at a time. Maybe M.B.Doc has some other ideas on some of these.

After some research I got the brights to faintly blink a couple of times by 'vigorously exercising' the stalk back and forth which leads me to believe the combo switch is bad. Tommorrow while replacing the evap temp sensor I'll spray some contact cleaner into the switch to see if it helps. Thanks guys for the suggestions. :)

if the fuses are powered when you are asking for hi-beams then the combi switch is GOOD.
That suggests the problem is either the "lamp monitor" computer OR at the lights themselves.

Possibly the lamp monitor computer is floating in water.

It is located under the door sill plate on the drivers side at the point whwer the front door meets the front side panel.

I went back to the fuse box today to check the voltage and had zero (0) at both fuses! Checked again a couple of mins later and had 12.1 at both :confused: Put both fuses back in and both sides high beams lit so I obviously have a combo switch that's heading (went) south.

After replacing the evap temp sensor today it looks like I'm cleaning up after the previous owner and still not done. :rolleyes:

Thanks DOC for the spot on advice....