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Funny electrical fault

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6 hours ago, Mannmade said:

So today I noticed my e39 thinks she's a police car




There is no fault. Someone has fitted LED halo bulbs to your car. E39s cold check your bulbs by giving a short burst of power to all the bulbs, and if it senses one is faulty it will warn you before you even turn on your lights. Normal incandescent bulbs don't light when the car is doing the cold checks because the power sent isn't long or high enough. However, they will light up LEDs because of the LED's instant on/off nature. 

The only way to "fix" it is to code out the cold checking on your LCM or fit expensive LEDs that don't flash. The latter is a bit of a trial and error because even some of the £33 bulbs from eBay flash. The only bulbs that I have seen that don't flash during cold checking are MTEC bulbs but they normally go for +-£70 which is overpriced IMO. 

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You can 'fix' the problem with a couple of relays; just wire the relays onto the back of the bulbs and then the LCM will 'see' the resstance of the relay coil and think all is well and the relays will switch on the power to the bulbs. 


Have a search with 'angel', 'led' and 'relay' on the E39 section and you should find it.


Edit: here's the page....



Edited by sharkfan

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3 hours ago, Mannmade said:

Like I say other than that they work perfectly I actually quite like it. Adds a bit of character 

 Until someone thinks you're flashing your lights at them, and pulls out in front of you :(


It does it on occasion as you drive along too.


You can only code it out on an LCM4.

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