"Check Side Lights" error, but all bulbs are working
 

Started yesterday. Whenever I turn on either the parking lights or the headlights, the error pops up. But all the bulbs front and rear are working fine.

This may sound nuts, but are the lights on the fenders (behind the front wheels) supposed to light up with the marker lights or just the blinkers? I never paid attention before. But mine only flash with the blinkers, do not light up with the markers. Could that be it?

If not, what other electrical gremlin has my X5 been afflicted with this month?

They flash with the blinkers only. One of those sidemarker bulbs could be dead...

Thanks, wasn't sure. Never looked at them before. But at the moment they both flash with the blinkers just fine.

Our x5 did the same thing Monday, I thought the front right turn signal bulb was out......took the bulb out and it appeared fine, it was not working, cleaned up everything and dabbed on a little dielectric grease and its perfect now.....no messages and everything works.

OK, my BMW electronics think they're old British Lucas electronics. After 3 days of living with the warning light, and not changing a think, went out this morning and all is well. Went out at lunch time to check again, and still no idiot light.

Self healing electrics?

Yeah, when it gets cold our BMW's will do weird s#!t. It's a mystery.

Lucas - Prince of Darkness

This is common problem on E53 X5. The bulb holder develops some kind of oxidation hence poor contact. I took out the bul-holder, snad paper the thing and layer a thin solder tin on it. No more false messages and it's been solid for 9 mo now.

Yup. And of course you know why the British drink warm beer? Lucas made refrigerators too.

All my MG's and Triumphs were electrical nightmares.

I have the same symptoms, but a differrent diagnose.

both of the front signals work, but the right one does not light up with the light switch in he parking position as the left one does.

I cleaned the connectors with a fine grit sand paper and swapped the bulbs and fittings from side to side. Still nothing. That made we wonder if there is some other issue...I measured the voltages from pins on both sides: a little over 10V on the left side and nothing on the right side.

I have not checked if there are more than two leads (positive and ground) going to the signal/side marker, but i suspect not. So there must be a light cotrol module somewhere in this car.

Any thoughts?