I have had noticed flat spots on my R52 Cooper S Convertible for a month now. Yesterday whilst in traffic, noticed my temp gauge right at the top in red and could hear the fan running full speed. No engine light. Scanned it and it displayed P1617. Cleared fault and fault seemed gone.

Today again fault has come up whilst at the traffic lights. If I switch the engine off and on again, problem goes away only to come back again after a few minutes. This time it was accompanied with the engine light on. Scanned for codes again and this time showing P1617 and P0118.

I understand P1617 to be Electronic Control Module H Bridge
Controller and P0118 to be Engine Coolant Temperature Circuit
High.

Has anyone else come across this problem and if so what was the solution? What is the H Bridge Controller and where do I start investigating? As for the P0118 code, Circuit High means high resistance or high voltage?

Any help appreciated.

 

I am so hoping its not a faulty DME. If P0118 refers to a faulty ECT, the input signals fed to the DME affecting the fueling and can explain the flat spots. If the The H bridge is anything to do with the throttle actuator, the ECT will have some effect on the throttle actuator (input affects the output) and perhaps really there is one fault and not two. Just that one fault is bringing up the other code. However if the ECT is faulty, it does not explain why after I switch engine off and immediately start it up again, the fault goes away for a few minutes. The resistance within the sensor will not change that quick. This then leads me to think the DME is playing up. This is all theoretical thinking. I have not even started looking into it but wanted some suggestions before attacking.