Theory Of Operation

The Transmission Control Module (TCM) measures the actual solenoid voltages and compares them to calibrated values to identify the following electrical failures:

• Short to battery
• Open circuit
• Short to ground

When the solenoid is switched on (i.e. commanded control value is 100%), the diagnostic can not distinguish between short to ground and open circuit. In that case, the Application-Specific Integrated Circuit (ASIC) status information is used to detect the failure.