My mechanic plugged a machine in the dash and it kept throwing out numerous codes which the mechanic told me was saying it was a bad ECM. so I sent the ECM to a company in illinois who checked it out and said that there was nothing wrong with the ECM. The ECM tech called my mechanic to discuss what codes the mechanic found and the ECM tech stated that those codes identified by my mechanic are not even codes for a cummins motor.
One of the codes identified a problem with crankcase positioning sensor. mechanic replaced this and codes kept indicating it was bad. That was part of reason mechanic said it had to be the ECM.
I plan to give this information to my mechanic on monday.
Also was wondering what you thought of possibility this could be a sensor problem.? Is the sensor the same for both the high coolant temperature and low coolant level as mentioned above?