GM Service Manual Online
For 1990-2009 cars only

Condition

Action

DEFINITION: Engagement time from park or neutral to reverse is not within specifications

Fluid level low and/or contaminated with water or engine coolant

    â€¢ Perform Transmission Fluid Check .
    â€¢ If contaminated with engine coolant replace transmission.

Fluid is burnt

    â€¢ Inspect transmission oil cooler system for restricted or kinked lines.
    â€¢ Flush system. Refer to Transmission Fluid Cooler Flushing and Flow Test .

Unit filled with wrong type of fluid

Drain and fill with proper type of fluid.

Input Speed Sensor (76)

    â€¢ Perform electrical function check on the input speed sensor (76).
    â€¢ Replace input speed sensor (76) if failed.

Valve body (39)

Replace valve body (39).

Internal transmission part failure

    â€¢ Disassemble the transmission and inspect the following:
       - Clutch assemblies, O-rings cut or damaged, clutch disc failure
       - Fluid pump wore or scored components
    â€¢ Replace transmission if any parts are faulty.