BMW M3 Coolant Sensor Issue

[terence.uchong]

Hi,

So I recently bought a BMW M3 and it came with a weird issue, for some odd reason the car wouldn't start unless the coolant temperature sensor connector was removed. I have taken it to the local mechanics as there is no official dealership where I live but the issue still remains. Being an engineer myself I tried to figure out whats wrong and have found that the sensor outputs the correct temperature of water and when the connector is removed the indicated temperature drops to a certain value.

I read on a few forums that the issue might be battery related and have myself replaced the battery to an original BMW 90aH AGM Battery as per the manual and online recommendations and also registered the battery with the ECM using a Maxis Scanner Tool.

Any help in this regard would be greatly appreciated!


Terence.