Front running/marker lights out
My front running lights (Amber next to headlights) and marker lights on side of front
fenders are out but when I cycle the door locks with the key fob they flash on momentarily
so I know the bulbs/fuse are good. Tail lights are fine. Turn signals work. Any idea what
could make them all go out if not fuse ?
4 Answers
When they flash, you know that the door lock fuse is good. They could have a separate source of power when used as the running lights. Checking fuses is cheap and easy. Use a meter. One lead clips to ground. Touch the other lead to the small section of exposed metal on the face of the fuse. A good fuse has the same reading on both sides. You will have to turn the key on to read the ignition circuit fuses.
Did you recently change anything electrical on the car? The3 Bosch wiring harness is all multi-plexed and one thing giving the incorrect feedback will cause other, seemingly random and unrelated items to malfunction.
Hi- Thanks for the reply. I have changed a couple of things but not sure I know exactly when the lights went out relative to timing of the changes... but it was definitely sometime after both. I had to change one of the electronic control boxes for the Xenon headlights and also had to repair part of the harness under the front skirt that goes to the fog lights and also has a lead for the outside air temperature themocouple/sensor ... the harness drooped down and got road rash thru the insulation and shorted out ... I repaired it by splicing in new pieces of wire (soldered) and wrapping it back up. I knew it had gone bad because the outside air temp. reading went bad on the dash ... after I repaired it the reading came back to normal and the fog lights worked again. Do you think any of these could have started the problem ? Ho do I check the multiplexed harness ? Thanks, Bob
Checking the harness is, unfortunately, difficult. Using the wrong gauge of wire would affect the feedback. Your best bet, on these cars, is to buy the replacement harness for the part that is damaged. We have this same problem with my Mom's 1990 Volvo. I keep threatening to go to Painless Electronics and getting a new harness for the entire car.