I am New owner of 06 523i. Yesterday, stuck in traffic. Warning message come up “engine-overheated, stop-it and call for help”. I have done some check/test. Cooling level is OK, no leak. The electrical water pump is working. I monitored the temperature up to almost 120°C, and the fan did not starts. Just after I stopped the engine, starts the fan. I repeated the test twice with the same result. It seems rare to me that the fan do not work while the engine is on and hot. Please does someone know a solution to that overheating problem? I will be grateful for any help and advices.

 

i had a similar problem years back on a car much less complex than a BMW (a Jeep).

my car was overheating and I also suspected that the fan was not running properly. it turned out that it was a coolant temperature sensor that was faulty and was not sending the signal to the fan to turn on. i'm not sure if the E60 has such a sensor, but it might be worth exploring.

 

BostonJon Thanks for replaying me. I will report back the findings letter.

 

BostonJon A New thermostat and new water pump helped to get the car on the road.