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For 1990-2009 cars only
Makes 🢒 Holden 🢒 2005 🢒 Commodore Executive 🢒 Transmission/Transaxle 🢒 Automatic Transmission - 4L60-E/4L65-E 🢒 DTC P2764

DTC P2764 V6

DTC Description

This diagnostic procedure supports DTC P2764 Torque Converter Clutch (TCC) Pressure Control (PC) Solenoid Control Circuit Low Voltage.

Circuit Description

The torque converter clutch pulse width modulation (TCC PWM) solenoid valve controls the fluid acting on the converter clutch valve. The converter clutch valve controls the TCC application and release. The solenoid attaches to the control valve body within the transmission. The solenoid receives voltage through ignition 1 voltage circuit (circuit 339). The transmission control module (TCM) controls the solenoid by providing a ground path on the TCC PWM solenoid valve control circuit (circuit 422). Current flows through the solenoid coil according to the duty cycle, percentage of on and off time. The TCC PWM solenoid valve provides a smooth engagement of the TCC by operating during a duty cycle percent of on time.

When the TCM detects a continuous open or short to ground in the TCC PWM solenoid valve control circuit, then DTC P2764 sets. DTC P2764 is a type A DTC.

Refer to Automatic Transmission Controls Schematics , Automatic Transmission Inline 20-Way Connector End View, Automatic Transmission Internal Connector End Views , Automatic Transmission Control Module Connector End Views , and Automatic Transmission Related Connector End Views to aid in diagnosis.

Conditions for Running the DTC
    • The system voltage is 8-18V.
    • The engine speed is 500 RPM for 5 seconds.

Conditions for Setting the DTC

DTC P2764 sets when either of the following conditions occurs for 5 seconds:

    • The TCM detects an open in the TCC PWM shift solenoid valve circuit when the TCC PWM is commanded on.
    • The TCM detects a short to ground in the TCC PWM shift solenoid valve circuit when the TCC PWM is commanded on.

Action Taken When the DTC Sets
    • The TCM requests the ECM to illuminate the check powertrain icon during the second consecutive trip in which the Conditions for Setting the DTC are met.
    • The TCM commands maximum line pressure.
    • The TCM freezes transmission adaptive functions.
    • The TCM inhibits TCC engagement.
    • The TCM inhibits 4th gear if in hot mode.
    • At the time of the first failure, the TCM records the operating conditions when the conditions for setting the DTC are met. The TCM stores this information as a Failure Record.
    • At the time of the second failure, the ECM records the operating conditions when the conditions for setting the DTC are met. The ECM stores this information as a Freeze Frame.
    • The TCM stores DTC P2764 in TCM history during the second consecutive trip in which the conditions for setting the DTC are met.

Conditions for Clearing the DTC
    • The ECM turns off the check powertrain icon after the fourth consecutive drive trip in which the TCM does not send a check powertrain icon illumination request.
    • Tech 2 can clear the DTC.
    • The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without a non-emission related diagnostic fault occurring.

Test Description

the following numbers refer to the step numbers in the diagnostic table:

4 Checks the ability of the TCM to control the solenoid.

5 Checks for supply voltage to the TCC PWM solenoid valve.

6 Checks the ability of the TCM and wiring to control the ground circuit.

8 Checks the resistance of the control valve body wiring harness and the TCC PWM solenoid valve.

9 Checks if the TCC PWM solenoid valve or control valve body wiring harness is shorted to the transmission housing.

13 Checks if the control valve body wiring harness is shorted to ground.

14 Checks if any of the other solenoids in the transmission are shorted to ground.

Step

Action

Yes

No

1

Has the Diagnostic System Check been performed?

Go to Step 2

Refer to Diagnostic System Check - Automatic Transmission

2
  1. Connect Tech 2 to the DLC.
  2. Turn on the ignition, with the engine off.

    3. Important: Before clearing the DTC, use the Tech 2 Freeze Frame/Failure Record in order to record the transmission parameters at the time the DTC set. Using Tech 2 to clear the DTC(s) erases the Freeze Frame/Failure Record records from the TCM.

  3. On Tech 2 select: Transmission/Automatic Transmission/Diagnostic Trouble Coeds/Freeze Frame.
  4. Select the relevant DTC and note the parameters at the time of the DTC setting.
  5. On Tech 2 select: Diagnostic Trouble Codes/Clear Engine and Transmission DTCs.
  6. Follow the instructions on Tech 2 and clear the DTCs.

    7. Are any of the following DTCs also set?

    • P0787
    • P0973
    • P0976
    • P2769

Go to Step 3

Go to Step 4

3

Inspect fuse F8 and check if it is blown, refer to Electrical Center Identification Views.

Is the fuse blown?

Replace the fuse

Go to Step 12

Go to Step 5

4
  1. On Tech 2 select: Transmission/Automatic Transmission/Miscellaneous Tests/TCC PWM solenoid.
  2. With Tech 2 command the TCC PWM solenoid ON and OFF three times.
  3. On Tech 2 select: Data Display/TCC Data.

Does Tech 2 display the TCC Duty Cycle Circuit as Okay?

Check for an intermittent fault in the circuit, refer to Testing for Intermittent Conditions and Poor Connections

Go to Step 5

5
  1. Turn off the ignition.
  2. Disconnect connector X121-X1 from the transmission.

    3. Important: Additional DTCs may set.

  3. Install Tool No. J 44152 Jumper Harness (20 pins) on to the harness connector X121-X1.
  4. Turn on the ignition, with the engine off.
  5. Using a test lamp, probe between connector X121-X1 pin E and a known ground.

Does the test lamp illuminate?

Go to Step 6

Go to Step 15

6
  1. Using a test lamp, probe connector X121-X1 pin E with the ground lead to connector X121-X1 pin B.
  2. On Tech 2 select: Automatic Transmission/Miscellaneous Tests/TCC PWM Solenoid.
  3. With Tech 2 command the TCC PWM Solenoid On and Off three times.

Does the test lamp turn on and off with each command?

Go to Step 8

Go to Step 7

7

Is the test lamp always illuminated?

Go to Step 16

Go to Step 17

8
  1. Remove Tool No. J 44152 from the harness connector X121-X1 and install on to the transmission connector X121-X1.
  2. Using a multimeter set to measure resistance, probe across transmission connector X121-X1 pins E and U.

Does the multimeter display 10-15Ω?

Go to Step 9

Go to Step 10

9

Using a multimeter set to measure resistance, probe between:

    • Transmission connector X121-X1 pin E and a known ground.
    • Transmission connector X121-X1 pin U and a known ground.

Does the multimeter display greater than 250kΩ in both instances?

Check for an intermittent fault in the circuit, refer to Testing for Intermittent Conditions and Poor Connections

Go to Step 11

10
  1. Remove Tool No. J 44152 from the transmission.
  2. Gain access to the TCC PWM solenoid and the control valve body wiring harness, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness.
  3. Disconnect the internal connector form the TCC PWM solenoid.
  4. Using a multimeter set to measure resistance, probe across the TCC PWM solenoid pins.

Does the multimeter display 10-15Ω?

Replace the control valve body wiring harness, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness

Go to Step 19

Replace the TCC PWM solenoid, refer to Transmission Fluid Pressure Manual Valve Position Switch Logic

Go to Step 19

11
  1. Remove Tool No. J 44152 form the transmission.
  2. Gain access to the TCC PWM solenoid and the control valve body wiring harness, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness.
  3. Using a multimeter set to measure resistance, probe between each of the TCC PWM solenoid pins and a known ground.

Does the multimeter display 250kΩ in both instances?

Replace the control valve body wiring harness, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness

Go to Step 19

Replace the TCC PWM solenoid, refer to Transmission Fluid Pressure Manual Valve Position Switch Logic

Go to Step 19

12

Test circuit 339 for a short to ground between connector X121-X1 pin E and the splice.

Did you find and correct the condition?

Go to Step 19

Go to Step 13

13
  1. Gain access to the control valve body wiring harness, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness.
  2. Test for a short to ground in the control valve body wiring harness.

Did you find a short to ground condition?

Replace the control valve body wiring harness, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness

Go to Step 19

Go to Step 14

14
  1. Test each solenoid for a short to ground.
  2. Replace the faulty solenoid as necessary.

Did you complete the replacement?

Go to Step 19

--

15

Test circuit 339 for an open circuit between connector X121-X1 pin E and the splice.

Did you find and correct the condition?

Go to Step 19

--

16

Using a multimeter, test circuit 418 for a short to ground.

Did you find and correct the condition?

Go to Step 19

Go to Step 20

17

Using a multimeter, test circuit 418 for an open circuit.

Did you find and correct the condition?

Go to Step 19

Go to Step 20

18

Replace the TCM, refer to Transmission Control Module Replacement.

Did you complete the replacement?

Go to Step 19

--

19

Perform the following procedure in order to verify the repair:

  1. On Tech 2 select: Diagnostic Trouble Codes/Clear Engine and Transmission DTCs.
  2. Follow the instructions on Tech 2 and clear any DTCs.
  3. On Tech 2 select: Data Display/TCC Data.
  4. Drive the vehicle in D4 and ensure the TCC Duty Cycle Circuit parameter displays Okay for 5 seconds.
  5. On Tech 2 select: Diagnostic Trouble Codes/Read DTC Information.

Has DTC P2764 set?

Go to Step 2

Go to Step 20

20

On Tech 2 select: Diagnostic Trouble Codes/Read DTC Information.

Does Tech 2 display any DTCs you have not diagnosed?

Refer to Scan Tool Data List

System OK

When all diagnosis and repairs are completed, check the system for correct operation.