GM Service Manual Online
For 1990-2009 cars only

DTC Description

The torque converter clutch (TCC) solenoid valve is an electrical device that is used with the torque converter clutch pulse width modulation (TCC PWM) solenoid valve in order to control TCC apply and release. The TCC solenoid valve attaches to the transmission case assembly extending into the pump cover. The TCC solenoid valve receives voltage through ignition voltage 1 circuit (circuit 339). The transmission control module (TCM) controls the solenoid by providing the ground path on the TCC solenoid valve control circuit (circuit 422). The TCM monitors the throttle position (TP) voltage, the vehicle speed and other inputs in order to determine when to energize the TCC solenoid valve.

Important: The TCC solenoid valve is part of the control valve body wiring harness. To replace the solenoid valve, the control valve body harness must be replaced.

When the TCM detects a continuous open or short to ground in the TCC solenoid valve control circuit, then DTC P2769 sets. DTC P2769 is a type B 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 8-18 V.
    • The engine speed is 500 RPM for 5 seconds.

Conditions for Setting the DTC

DTC P2769 sets when either of the following conditions occurs for 5 seconds:

    • The TCM detects an open in the TCC solenoid valve circuit when the TCC is commanded on.
    • The TCM detects a short to ground in the TCC shift solenoid valve circuit when the TCC 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 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 P2769 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.

Diagnostic Aids

With the TCC engaged, the TCC slip speed should be -20 to +40 RPM.

Test Description

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

4 Checks for supply voltage to the 3-2 SS Valve.

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

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

8 Checks if the TCC solenoid valve or control valve body wiring harness is shortened to the transmission housing.

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

11 Checks whether 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.

  4. On Tech 2 select:
  5. Transmission / Automatic Transmission / Diagnostic Trouble Codes / Freeze Frame.

  6. Select the relevant DTC and note the parameters at the time of the DTC setting.
  7. On Tech 2 select:
  8. Diagnostic Trouble Codes / Clear Engine & Transmission DTCs.

  9. Follow the instructions on Tech 2 and clear the DTCs.

Are any of the following DTCs also set?

    • P0787
    • P0973
    • P0976
    • P2764

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 9

Go to Step 5

4

  1. Turn off the ignition.
  2. Disconnect connector X121 - X1 from the transmission.
  3. Important: Additional DTC may set.

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

Does the test lamp illuminate?

Go to Step 7

Go to Step 12

5

  1. Using a test lamp, probe connector X121 - X1 pin E with the ground lead connector X121 - X1 pin T.
  2. On Tech 2 select:
  3. Automatic Transmission / Miscellaneous Tests / TCC Solenoid

  4. With Tech 2 command the TCC Solenoid On and Off three times.

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

Go to Step 7

Go to Step 6

6

Is the test lamp always illuminated?

Go to Step 13

Go to Step 14

7

  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 T.

Does the multimeter display 21-33 Ω?

Go to Step 8

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

Go to Step 16

8

Using a multimeter set to measure resistance, probe between:

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

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

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

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

Go to Step 16

9

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 16

Go to Step 10

10

  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 and TCC solenoid, refer to Torque Converter Clutch Pulse Width Modulation Solenoid, Torque Converter Clutch Solenoid, and Wiring Harness

Go to Step 11

11

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

Did you complete the replacement?

Go to Step 16

--

12

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 16

--

13

Using a multimeter, test circuit 422 for a short to ground.

Did you find and correct the condition?

Go to Step 16

Go to Step 15

14

Using a multimeter, test circuit 422 for an open circuit

Did you find and correct the condition?

Go to Step 16

Go to Step 15

15

Replace the TCM, refer to Transmission Control Module Replacement.

Did you complete the replacement?

Go to Step 16

--

16

Perform the following procedure in order to verify the repair:

  1. On Tech 2 select:
  2. Diagnostic Trouble Codes / Clear Engine & Transmission DTCs.

  3. Follow the instructions on Tech 2 and clear any DTCs.
  4. On Tech 2 select:
  5. Miscellaneous Tests / TCC Solenoid.

  6. Drive the vehicle in D4. With Tech 2 command the TCC solenoid valve On for 5 seconds and Off for 5 seconds.
  7. On Tech 2 select:
  8. Diagnostic Trouble Codes / Read DTC Information.

Has DTC P2769 set?

Go to Step 2

Go to Step 17

17

On Tech 2 select:

Diagnostic Trouble Code / 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.