BMW E32 lighting fault warning and lights not working
Why does the E32 dashboard show a light failure warning even though the lights work?
The cause is often the light box's yellow relay, whose solder joints or pins have cracked. The fault can come and go randomly, and sometimes it shows only for the lights on one side. Resoldering usually fixes the fault.
A headlight or tail light does not work even though the bulb and fuse are fine - what is wrong?
Possible causes are the light module, or LKM, the yellow relay and their solder joints. The solder joints of an old LKM can be checked, and a worn module is often fixed by replacing it with a used one. The LKM comes off by pulling and wiggling it, as it has no locking tabs.
Why do the tail light fuses blow as soon as the car is started?
The cause can be a short circuit: a tail light wire may have been caught under a fixing screw and burnt. Remove the wire from under the screw and check its condition. Oxidised bulb sockets and connectors can also cause contact problems.
Why does the number plate light give a fault warning?
LED bulbs cause the warning because the car's lamp monitoring does not detect their low current draw. Ordinary bulbs stop the warning. LEDs need a canbus version with a resistor. Also check oxidised connections and earths.