XSeries-forum

I used BMW Scanner 1.4.0 to turn off the cold check on my LED registration plate lights in order to stop them flashing. I noticed some other cold checks were already off so I turned them on again. And then started getting errors on the dash. Centre brake light (which started flashing once I'd enabled it), left rear tail light, right rear tail light. Why would these be off? Both tail lights (upper and lower) in each rear lamp are working and are not LED.

Could be a high resistance connection on the light unit.
The lights will still work but the LCM will see a potential problem

The connections to the rear lights are a particular weak point

Understood. I'd assumed that the rear lamp corrosion issue would mean the lamps don't work. Many thanks.

BMW's work in mysterious ways....
Especially the X5...

My warning comes up quite a bit but all lights are working.

indeed..

on a previous 3 series i've had a tail light issue indicated but all lights working - turned out to be a corroding wire connection to the bulb holder. bit if soldering sorted it out.

on the X i once noticed that one of the tail lights was dimmer than the other but no light fault was indicated. removed the bulb and sure enough the light fault indicator came up. i figured it was either the bulb or the connection to the holder (way the holder is designed to make contact with the housing its surely a potential failure point over many years.. ) cleaned the holder contacts onto the housing and sure enough that fixed the issue..