Trailer detection?
 

Hi peeps, im still having some bulb and warning issues with my LED lighted trailer and my 2001 X5. I have fitted an OEM hitch kit from ECS with all the right harnesses and modules.
I even bought a special external module to fix this: Linear Electronic Design | Home
But alas I still get the 'CHECK TRAILER LIGHTS' warning on the dash! awesome....

If I turn 'Warn Monitoring' off for the trailer...will that mean that the X5 wont know there is a trailer at all and do the necessary adjustments (or whatever it does) when towing a trailer?

In a 2001 E53 what exactly happens when a trailer is attached?
I know the rear PDC should be disabled.
anything else?

The only other adjustment is turning off the rear PDC. You can check if that functions as designed quite easily, by putting it in reverse with the trailer connected.

There is a trailer stability control mode in the DSC program, but that wouldn't depend on bulb warning lights IMO.