The standard reading should be about 60 ohms. Check The PCM The ODB II diagnostic scanner is used to diagnose the engine control unit. The scan tool connects to the vehicle's diagnostic port. Once ...

A faulty or malfunctioning transmission can trigger the check engine light for a handful of reasons, including things like an overheating gearbox or issues with the transmission control module (TCM).

If the Engine Control Module is not properly recalibrated, the Cadillac CT5 may fail to illuminate the Check Engine light if there is a catalytic converter fault.