GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P2762:  Torque Converter Clutch (TCC) Pressure Control Solenoid System Performance

DTC P2763:  Torque Converter Clutch (TCC) Pressure Control Solenoid Control Circuit High Voltage

DTC P2764:  Torque Converter Clutch (TCC) Pressure Control Solenoid Control Circuit Low Voltage

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

TCC Pressure Control Solenoid

P2764

P2763

P2763

P2762

Typical Scan Tool Data

TCC PC Solenoid

Circuit

Grounded

Open

Shorted to Voltage

Operating Conditions: Engine running, normal operating temperature

Parameter Normal Range: OK

TCC PC Sol. CKT Status

Short to GND

Open/Short to Volts

Open/Short to Volts

Circuit/System Description

The torque converter clutch (TCC) pressure control solenoid is part of the control solenoid (w/body and TCM) valve assembly. The control solenoid (w/body and TCM) valve assembly has no serviceable parts. The TCM supplies 12 volts to the TCC pressure control solenoid through the high side driver circuit. The TCM controls the TCC solenoid through the TCC solenoid control circuit. The normally low TCC pressure control solenoid flows fluid to the TCC when commanded ON and exhausts fluid when commanded OFF. This allows the TCC solenoid to regulate the transmission fluid pressure to the TCC.

Conditions for Running the DTC

    • The engine run time is greater than 5 seconds.
    • The ignition voltage is between 9.0 volts and 19.0 volts.
    • The clutch PC solenoid 4 is commanded ON.
    • The suspect code (P02762, P02763 or P02764) has not failed this ignition cycled 19.0 volts.

Conditions for Setting the DTC

P2762

The TCM detects an internal electrical performance malfunction of the TCC pressure control solenoid circuit where the actual TCC pressure does not equal the commanded TCC pressure for 10.5 seconds or greater.

P2763

The TCM detects an internal high voltage electrical malfunction of the TCC pressure control solenoid control circuit for 4.4 seconds or greater.

P2764

The TCM detects an internal low voltage electrical malfunction of the TCC pressure control solenoid control circuit for 4.4 seconds or greater.

Action Taken When the DTC Sets

P2762

    • DTC P2762 is a Type C DTC.
    • The TCM freezes transmission adaptive functions.

P2763 and P2764

    • DTCs P2763 and P2764 are Type A DTCs.
    • The TCM inhibits 6th gear in Hot Mode.
    • The TCM inhibits TCC.
    • The TCM commands maximum line pressure.
    • The TCM freezes transmission adaptive functions.
    • MUMD inhibit action.

Conditions for Clearing the DIC/DTC

    • DTC P2762 is a Type C DTC.
    • DTCs P2763 and P2764 are Type A DTCs.

Diagnostic Aids

P2762

DTC P2762 detects an invalid voltage in the transmission line pressure variable bleed solenoid (VBS) control circuit.

P2763

DTC P2763 detects a continuous short to ground in the transmission line pressure VBS control circuit.

P2764

DTC P2764 detects a continuous open or short to voltage in the transmission line pressure VBS control circuit.

When attempting to set solenoid electrical DTCs, ensure the TCM is warmed up and the transmission is operated in 2nd gear long enough to ensure a 3°C (5°F) increase in TCM substrate temperature. This will place the TCM under the optimal conditions to test solenoid electrical DTCs.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics

Description and Operation

    •  Transmission General Description
    •  Transmission Component and System Description
    •  Electronic Component Description

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification

  1. Ensure the transmission fluid temperature is between 50-80°C (122-176°F).
  2. Perform the Control Solenoid Valve and Transmission Control Module Assembly Cleaning procedure to dislodge debris and free up valves.
  3. Operate the vehicle in 2nd gear long enough to ensure at least a 3°C (5°F) rise in TCM temperature, then operate the vehicle to ensure TCC engagement for 5 seconds.
  4. Verify that the scan tool data parameter, TCC PC Sol. CKT Status, displays OK.
  5. If not the specified value, replace the control solenoid (w/body and TCM) valve assembly.
  6. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

       Important: Before replacing the TCM, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection .

    • Refer to Control Module References for control solenoid (w/body and TCM) valve assembly replacement, setup, and programming.
    • Perform the Service Fast Learn Adapts following all transmission related repairs.