on my x300 im having some turn signal issues, my left turn signal is very dim on the front bumper and the fog lamp lights up a little with the blinker. I have checked all of the bulbs and they are working. if i unplug the left foglight i get no front turn signals and a fast blinker but the other lights are bright like they should be. I also occasionally get a fast blinker on the left side while driving even though all the lights still blink. on the right side the small light on the side of the bumper does not work, the bulb and socket were tested and work. neither fog lamp works with the fog lamp switch. this is a very confusing issue and any help is appreciated

 

This is the result of a bad earth connection somewhere. It is more often seen with rear lights when indicator on and you press the brake the indicator stops flashing and the brake light will flash instead and sometimes the tail/rear light goes out. I have checked the wiring diagram and suggest you check which is the +12v feed to the indicator and then conect the other one directly to earth/chassis. From the wiring diagram the black cable is the return to earth/chassis.
BW
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