GM Service Manual Online
For 1990-2009 cars only

Checks

Cause

2-3 Solenoid (311)

Check for DTCs.

    â€¢ Stuck Off
    â€¢ Loose connector
    â€¢ No voltage to the solenoid
    â€¢ Solenoid O-ring failure
    â€¢ No PCM signal to the solenoid

2-3 Shift Valve (312)

Stuck

Quad Driver Module

Failed

Check the PCM for current DTCs.