GM Service Manual Online
For 1990-2009 cars only

Checks

Causes

3rd Clutch Filter Screen

Clogged

Brake Switch

    • Contact corroded
    • Poor connection
    • Pinched wire
    • Misadjusted
    • No supply voltage

PCM

No signal to solenoid

TCC Control Valve

Stuck OFF due to sediment or undersized bore

TCC Feed Valve

Stuck OFF due to sediment or undersized bore

TCC Regulating Valve

Stuck OFF due to sediment or undersized bore

TCC Solenoid Valve

    • Stuck OFF
    • O-ring failed
    • No voltage to solenoid
    • Poor connection

TFT

Incorrect reading (cold)

Torque Converter

    • Ballooning
    • TCC not engaging fully or slipping

Turbine Shaft to Drive Sprocket Support O-Ring Seal

    • Damaged or leaking
    • Worn