Right headlamp only comes on when right turn signal invoked (& right plate bulb)
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Joined: Jul 2015
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2001 ML 55 AMG, 2002 ML500, W203, W163 320
Right headlamp only comes on when right turn signal invoked (& right plate bulb)
I have a friend with a w203 with weird electrical problems.
1.) when facing the front of the car from outside, when the lights are turned on, only the drivers bulb comes on. the passenger doesn't. The only way to get the outer bulb (theres a top, outer and inner bulb) on is to turn the right turn signal on. then it blinks. Other than this even with high beams it doesn't turn on.
The inner bulb (closest to hood latch) on the passenger side only turns on when the high beam is on, but not the low or with the remote lock/alarm comes on.
2.) the right license plate light is out. I replaced with a new Sylvania LED bulb from a w163 and it didn't turn on. I didn't try cleaning the contacts or squeezing for a tighter fit yet but it seems it may stem from something else.
I checked all fuses under the hood (Closest to driver door) and the one inside by the drivers door with a multimeter and changed one that was 20 volts underneath the hood. I haven't checked the other 2 (or 3????) fuse boxes yet or gotten the fuse map diagram, but I figure headlights would be under the hood?
any help or advise would be appreciated!
1.) when facing the front of the car from outside, when the lights are turned on, only the drivers bulb comes on. the passenger doesn't. The only way to get the outer bulb (theres a top, outer and inner bulb) on is to turn the right turn signal on. then it blinks. Other than this even with high beams it doesn't turn on.
The inner bulb (closest to hood latch) on the passenger side only turns on when the high beam is on, but not the low or with the remote lock/alarm comes on.
2.) the right license plate light is out. I replaced with a new Sylvania LED bulb from a w163 and it didn't turn on. I didn't try cleaning the contacts or squeezing for a tighter fit yet but it seems it may stem from something else.
I checked all fuses under the hood (Closest to driver door) and the one inside by the drivers door with a multimeter and changed one that was 20 volts underneath the hood. I haven't checked the other 2 (or 3????) fuse boxes yet or gotten the fuse map diagram, but I figure headlights would be under the hood?
any help or advise would be appreciated!
MBWorld Fanatic!
Joined: Jan 2005
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From: Orange County
2005 C Wagon (No snickering please!)
Follow the brown wire from the headlight assembly to where it connects to the chassis. Take off the nut and make sure all the ring lugs are clean and shiny. Make sure the chassis connection is free of dirt, grease, rust or other contaminate. Use an emery board to spiff it up if necessary. Make sure the nut is tight.
Also check the brown wire into the headlight assembly for cleanliness and good contact. Use isopropyl (99%) alcohol sparingly to clean it.
There are no fuses for the headlights. They are controlled electronically by the Front SAM. Your problem sounds like a poor ground connection to the headlight module. When the lamp lights it is finding a ground through the smaller bulb.
A couple of minutes with a volt meter in the hands of a good electrician will sort this problem.
Also check the brown wire into the headlight assembly for cleanliness and good contact. Use isopropyl (99%) alcohol sparingly to clean it.
There are no fuses for the headlights. They are controlled electronically by the Front SAM. Your problem sounds like a poor ground connection to the headlight module. When the lamp lights it is finding a ground through the smaller bulb.
A couple of minutes with a volt meter in the hands of a good electrician will sort this problem.
