Hi,

My 2003 R53 intermittently overheats when stopped. It seems like the cooling fan isn't coming on early enough? I usually turn off the engine and then I hear the fan come on and the temperature will start to drop. I'm thinking the temperature switch may be bad? Is there a secondary switch or relay that could cause this? I guess I can plug in my OBD sensor and see what the temperature that it sees is currently when it's overheating. There seems to be only one cooling fan? I know some cars have a second one that comes on when the A/C is turned on.

 

You need to do a search on 'Low Speed Fan Resistor . ." Likely explains your problem.

 

Flip on your ac and if the fan does not come on the low speed is having issues. Lots of discussion on the matter in the below thread. I have the resistor installed and it does work, I have posts in the thread about it.

https://www.northamericanmotoring.co...-solution.html