GM Service Manual Online
For 1990-2009 cars only

Check

Causes

DEFINITION: Transmission main line pressure that is determined to be high or low. Refer to Line Pressure Check.

Fluid Pump Assembly

    • Pressure regulator valve stuck
    • Pressure regulator valve spring
    • Line boost valve spring
    • Line boost valve or bushing stuck, damaged or incorrectly assembled
    • Pressure relief ball not seated or damaged
    • Pressure relief ball spring
    • Pump slide seal out of location
    • Fluid pump screen assembly plugged or damaged
    • Fluid pump rotor guide omitted or misassembled
    • Fluid pump rotor cracked or broken
    • Porosity in fluid pump
    • Fluid pump surfaces not flat
    • Excessive fluid pump rotor clearance

Fluid Filter

    • Intake pipe restricted ยท
    • Cracks in fluid filter
    • Fluid filter seal missing, cut or damaged

Control Valve Body Accumulator Assembly

    • Manual valve scored or damaged
    • Spacer plate or gaskets misassemble or damaged
    • Control valve top channel plate not flat
    • Control valve bottom channel plate not flat
    • Feed limit valve or spring stuck in the exhaust position

Pressure Control Solenoid Assembly

    • Contaminated
    • O-rings cut or damaged
    • Electrical connection

System Voltage

    • 12 Volts not supplied to transmission
    • Electrical short - pinched solenoid wire
    • Solenoid not grounded

Clutch Accumulator

Leaking

Inspect for active transmission DTCs

Transmission DTC default action active