2005 Uplander 3.5L. I am getting a check engine light with code P0128 "engine temperature has not increased and/or reached the correct level within a specified amount of time after engine startup". My guage on the dash reads normal and heat blows out perfectly. The coolant expansion tank looked a little low but the radiator was full and I added more coolant to the tank.

1. Are there two different sensors i.e. one for the dash and one for the computer?

2. Could this just be a thermostat?

Thanks
Doug
Doug

 

1.one sensor monitor coolant temp and info is sent from the ecm to the guage via serial data line communication

2.usually it is a thermostat issue.

 

What temp thormostat should be used in a 2005 Uplander?