GM Service Manual Online
For 1990-2009 cars only

Torque Converter Clutch (TCC) Stuck ON or OFF

Condition

Action

DEFINITION: Torque converter clutch (TCC) stuck ON or OFF

Torque Converter Assembly (1)

Perform an electrical performance test. If no concern was verified electrically, inspect the torque converter assembly (1) for signs of internal damage caused by an external issue such as mount bolts too long in length or thread repair. Replace the torque converter assembly (1) making sure that the correct flexplate mounting bolts are used.

External Control Valve Body Assembly (39)

    • 1-2,2-3, Reverse Shift solenoid Valve Assembly (S3) (300)
    • 3-4, 4-5 Shift Solenoid Valve Assembly (S4) (303)
    • TCC Lock Up Pressure Control Solenoid Valve Assembly (SLU) (339)

Verify that all solenoids respond electrically. If there is no response, perform an electrical diagnosis. If there are no electrical concerns, remove the solenoid valve assembly as needed, and inspect the solenoids O-ring seals, and bores for signs of damage and/or missing seals. If the valves responded electrically and there are no bore or seal concerns, replace assembly as required due to a possible internal mechanical concern and retest. If after replacing the valve assembly in question, a concern is still present, replace the complete control valve body assembly (39).

Internal Control Valve Body Assembly (39)

    • Secondary Regulator Valve (436)
    • U2 Shift Valve (392)
    • Solenoid Relay Valve (378)
    • Lock Up Relay Valve (415)
    • Lock Up Control Valve (454)

Remove the control valve body assembly to inspect the items listed. Inspect internal bores and valves for signs of wear and/or damage, including internal contamination. If unable to verify a repairable concern, replace the complete valve body assembly.