GM Service Manual Online
For 1990-2009 cars only

Third and Fourth Gear Operation

Checks

Cause

2-3 Shift Solenoid for OFF Failure

    â€¢ Foreign material and plugging in the filter
    â€¢ Insufficient force of the solenoid
    â€¢ 2-3 Shift Solenoid O-ring failure
    â€¢ 2-3 Shift Valve stuck in upshift position.
    â€¢ An open wire from the shift solenoid to the PCM
    â€¢ The PCM is not grounding
    â€¢ No supply voltage to the solenoid
    â€¢ Wires are not connected to the solenoid