GM Service Manual Online
For 1990-2009 cars only

Checks

Cause

Intermediate Clutch Plates (631, 632)

Seized

Direct Clutch Lube Feed

Blocked

Center Support Springs (635)

Jammed

Center Support Piston (636)

Jammed

1-2 Shift Solenoid Valve (313)

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

PCM

No PCM signal to the solenoid

Quad Driver Module

Failed

1-2 Shift Valve (314)

Stuck

Check the PCM for current DTCs.