GM Service Manual Online
For 1990-2009 cars only

Incorrect TCC Apply or Release

Checks

Cause

AT Output (Shaft) Speed Sensor Assembly (22)

    • Poor connection
    • Pinched wire
    • A broken coil wire
    • Incorrect air gap
    • Inadequate signal

Throttle Position Sensor

    • Poor connection
    • Pinched wire
    • Incorrect resistance

VCM/PCM

Failed

Automatic Transmission Fluid Pressure Manual Valve Position Switch (40)

    • Poor Connection
    • No signal to the VCM/PCM
    • Pinched wire

AT Fluid Temperature Sensor Assembly (332)

    • Poor Connection
    • No signal to the VCM/PCM
    • Incorrect Resistance
    • Pinched wire

Engine Coolant

No signal to the VCM/PCM

Brake Switch

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

Engine Ignition Module

Loss of signal or intermittent

Check the VCM/PCM for current DTCs

Only 2WD

  • Digital Ratio Adapter (DRAC)
    • Malfunction
    • Incorrect