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For 1990-2009 cars only
Makes 🢒 GMC_Truck 🢒 2009 🢒 Sierra Denali 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC P2761, P2763, or P2764

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 Descriptor

DTC P2761: Torque Converter Clutch (TCC) Pressure Control (PC) Solenoid Control Circuit

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

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

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Control

P2764

P2761

P2763

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Circuit/System Description

The torque converter clutch (TCC) pressure control solenoid controls pressure which is proportional to the current. The transmission fluid pressure from the TCC pressure control solenoid is directed to another valve which regulates the transmission fluid flow and pressure through the torque converter clutch valve to control the rate of TCC apply and release.

The transmission control module (TCM) provides B+ to the TCC solenoid, pressure control solenoid 1 (PCS1), and the main modulation/line pressure control solenoid (MAIN MOD) through a separate solid state device called high side driver 1 (HSD1). The TCM uses a low side driver to control the current flow to the TCC pressure control solenoid. The TCM controls the current to the solenoid by changing the amount of time that the low side driver is on.

Conditions for Running the DTC
    • No DTCs P0657, P0658, or P0659.
    • Battery voltage is greater than 9.0 V and less than 18 V.
    • Engine speed is greater than 200 RPM.

Conditions for Setting the DTC

P2761

This DTC sets when the TCM detects an open circuit on the TCC pressure control solenoid control circuit for greater than 3 seconds.

P2763

This DTC sets when the TCM detects a short to voltage on the TCC pressure control solenoid control circuit for greater than 1 second.

P2764

This DTC sets when the TCM detects a short to ground on the TCC pressure control solenoid control circuit for greater than 3 seconds.

Action Taken When the DTC Sets

P2761

    • The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL) on the second consecutive occurrence.
    • The TCC will not apply.
    • DTC P2761 is stored in TCM history.

P2763

    • The TCM requests the ECM to illuminate the MIL on the second consecutive occurrence.
    • The TCC will not apply.
    • DTC P2763 is stored in TCM history.

P2764

    • The TCM requests the ECM to illuminate the MIL on the second consecutive occurrence.
    • The TCC will not apply.
    • If the fault occurs while in a forward range, a shift to 1st, 3rd, or 5th range is made.
    • While diagnostic response is active, if the shift selector is moved to NEUTRAL, the transmission will shift to NEUTRAL. If the shift selector is moved to REVERSE, the transmission will shift to REVERSE. If the shift selector is moved to a forward range or to REVERSE and the transmission is compromised by overspeeding or direction change, the transmission will shift to NEUTRAL.
    • DTC P2764 is stored in TCM history.

Conditions for Clearing the DTC

DTCs P2761, P2763, and P2764 are Type B DTCs.

Diagnostic Aids

P2761

    • You may have to drive the vehicle in order to experience a condition.
    • If DTC P2761 is accompanied by DTC P0960, Main Modulation/Line Pressure Control (PC) Solenoid Control Circuit Open, and/or DTC P2727, Pressure Control (PC) Solenoid 1 Open , the open is most likely in the HSD1 circuit.

P2763 and P2764

You may have to drive the vehicle in order to experience a condition.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

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

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Verification
  1. Ignition ON, engine OFF, command the TCC Control Solenoid ON and OFF with a scan tool. Observe the operation of the TCC PC Sol. Pressure Command parameter. The TCC PC Sol. Pressure Command parameter should change from 0 kpa (0 psi) to 1600 kpa (232 psi).
  2. 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.

Circuit/System Testing
  1. Ignition OFF, disconnect the X175 harness connector at the transmission.
  2. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal L and ground.
    3. ⇒If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the TCM.
  3. Connect a test lamp between the control circuit terminal J and the B+ circuit terminal L.
  4. Ignition ON, command the TCC Control Solenoid ON and OFF with a scan tool. The test lamp should turn ON and OFF when changing between the commanded states.
    5. ⇒If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the TCM.
    ⇒If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the TCM.
  5. Remove the transmission oil pan. Refer to Oil Pan Replacement.
  6. Test the transmission internal B+ and control circuits for a short to voltage, short to ground, or an open/high resistance.
    7. ⇒If the circuits test normal, test or replace the TCC solenoid.

Component Testing

Static Testing

    Note: You must perform the Circuit/System Testing first.

  1. Ignition OFF, remove the TCC solenoid from the valve body. Refer to Control Valve Solenoid Replacement.
  2. Test for resistance between the control circuit terminal 2 and the B+ circuit terminal 1 of the TCC solenoid. Refer to Temperature Versus Resistance.
    3. ⇒If not within the specified range, replace the TCC solenoid.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Wiring Harness Replacement
    •  Control Valve Solenoid Replacement
    •  Control Module References for TCM replacement, setup, and programming

Repair Verification

If another DTC is present, refer to Diagnostic Trouble Code (DTC) List - Vehicle and perform the appropriate diagnostic procedure.