GM Service Manual Online
For 1990-2009 cars only

DTC Descriptor

This diagnostic procedure supports the following DTC:

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

Conditions for Running the DTC

    • Emergency mode is OFF.
    • System voltage is 10.2-15.5 volts.

Conditions for Setting the DTC

    • Torque converter clutch (TCC) pressure control (PC) solenoid feedback current is less than 0.092A for 12.5 seconds.
    • Torque converter clutch (TCC) pressure control (PC) solenoid feedback circuit indicates a continuous open or short to ground for 12.5 seconds.

Action Taken When the DTC Sets

    • TCM will request the illumination of MIL.
    • TCM records the operating condition when the Conditions for Setting the DTC are met. TCM stores this information as Failure Record.
    • TCM stores DTC in TCM history.
    • TCM turns Emergency mode ON.
    • When the Emergency mode is ON, the following conditions occur :
       - The transmission will operate in 4th gear when the transmission is shifted into D or M+ range.
       - The transmission will operate in 2nd gear when the transmission is shifted into 2 or M- range.
       - Learn control is disabled.
       - Lock up control is disabled.
       - Adaptive control is disabled.
       - N-D shifting is disabled.
       - ABS function is disabled.

Conditions for Clearing the MIL/DTC

    • The MIL turns OFF when no failure is detected for 3 consecutive driving cycles.
    • The scan tool can clear the DTC from the TCM history.
    • The TCM clears the DTC from the TCM history memory after 40 consecutive warm-up cycles without fault.

Cause of Failure

    • Wiring harness or connector between TCC lock up pressure control (PC) solenoid and TCM
    • TCC Lock Up Pressure Control (PC) Solenoid
    •  TCM

Step

Action

Values

Yes

No

1

  1. Turn the ignition OFF.
  2. Install the Scan tool.
  3. With the engine OFF, turn the ignition switch to the ON position.
  4. Select Store Freeze Frame/Failure Records from the Diagnostic Trouble Codes Information menu.
  5. Store Freeze Frame/Failure Records.
  6. Select Clear DTC Information from the Diagnostic Trouble Codes Information menu.
  7. Clear DTC Information.
  8. Perform one vehicle drive cycle.

Is the Malfunction Indicator Lamp (MIL) ON?

--

Go to Step 2

Repair the temporary connection failure of connector. Refer to Repairing Connector Terminals.

2

  1. Select Request DTC by Status from the Diagnostic Trouble Codes Information menu.
  2. Request DTC by Status.

Is DTC P2763 displayed?

--

Go to Step 3

Repair the temporary connection failure of connector. Refer to Repairing Connector Terminals.

3

  1. Turn the ignition OFF.
  2. Inspect the resistance between the vehicle harness and TCC lock up pressure control solenoid.
  3. Disconnect the TCM connector J1 (X-1) and inspect the resistance between the terminal 5 and 3.

Is the measurement within the specified value?

20°C (68°F)

5.0-5.6 Ω

Go to Step 4

Go to Step 5

4

  1. Estimate the failure of between the vehicle wiring harness connector and TCM.
  2. Inspect the connector. Refer to Repairing Connector Terminals.
  3. Inspect the connection condition between the connectors (C-1).

Is the connection condition OK?

--

Go to Step 6

Repair the wiring harness connectors.

5

  1. Estimate the failure of between the vehicle harness and TCC lock up pressure control solenoid.
  2. Disconnect the connector (X-3) of transmission wire and inspect the resistance between TCC lock up pressure control solenoid connector terminal 10 and 3.

Is the measurement within the specified value?

20°C (68°F)

5.0-5.6 Ω

Go to Step 7

Go to Step 8

6

  1. Replace the master TCM.
  2. Perform the reproducing test under user condition after confirming no DTC.

Is DTC displayed?

--

Repair the temporary connection failure of connector.

Replace the TCM.

7

  1. Estimate the failure of the vehicle wiring harness or between connectors.
  2. Inspect continuity and short circuit for the vehicle wiring harness and inspect the connection condition between connectors (C-3). Refer to Repairing Connector Terminals.

Is the condition OK?

--

Repair the temporary connection failure of connector.

Replace the vehicle harness or adjustment between connectors.

8

  1. Estimate the failure of transmission wire or between connectors of TCC lock up pressure control solenoid.
  2. Inspect the TCC lock up pressure control solenoid.

Is the problem found?

--

Replace the valve body assembly. No replacement of TCC lock up pressure control solenoid by itself. Refer to Control Valve Body Replacement.

Go to Step 9

9

  1. Estimate the failure of transmission wire.
  2. Inspect continuity and short circuit for the transmission wire and inspect the connection condition between connectors (C-5). Refer to Repairing Connector Terminals.

Is the condition OK?

--

Repair the temporary connection failure of connector.

Replace the transmission wire or adjustment between connectors.