540i error

[compmore]

i have a 94 540i and once i turn the headlights on i get a brake light error message.it then cycles thru saying dim light/number plate light etc r faulty.

have had an auto electrian check globes,earths etc and they can't find anything wrong.no prblems in day running only starts when headlights on

hope someone can give us an idea

[shogun]

Is the brake light off then when you get the warning?

[DaveVoorhis]

Assuming all the wiring and contacts are good, and you have proper bulbs, it might be a failure of the light control module (LKM) or the check control module (CCM).

[compmore]

Is the brake light off then when you get the warning?

most usally starts when i brake with headlights on

[compmore]

Assuming all the wiring and contacts are good, and you have proper bulbs, it might be a failure of the light control module (LKM) or the check control module (CCM).

thanks am starting to think must be sum computer module problem.guess it will b an expensive bmw dealer job

rgds,

geoff

[genphreak]

thanks am starting to think must be sum computer module problem.guess it will b an expensive bmw dealer job rgds, geoff

Mostly its not, the modules unplug and when you open them up they often reveal dry or damaged joints where relay pins are soldered. The occasinal module failiure happens, but its usually the years of use/heat the relays see that things go wrong. Just pull them and check them. plenty of info online about the LKM nad mustard relay repairs.