TCC Circuit Check: Notes

Fig 1: TCC Circuit Check Diagram

Courtesy of GENERAL MOTORS CORP.

TCC will engage under following conditions: vehicle speed is greater than 30 MPH, transmission is in 4th gear, engine and transmission are at normal operation temperatures, brake switch is closed, throttle position switch signal is steady, and no codes are stored.

1. This step tests TCC solenoid and circuits inside transmission for shorts.
2. This step tests for power to transmission connector.
3. This step tests for short to ground in circuit 422.
4. This step tests for PCM/TCM control of TCC.