GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Holden 🢒 2005 🢒 Caprice WL 🢒 Transmission/Transaxle 🢒 Automatic Transmission - 5L40-E/5L50-E 🢒 DTC P2763

Circuit Description

The Transmission Control Module (TCM) provides voltage to the Torque Converter Clutch Pulse Width Modulated (TCCPWM) solenoid valve through the High Side Driver 2 (HSD2). The TCM controls the on and off time of the solenoid by providing a ground through the Output Driver Module (ODM). The TCM uses a PWM duty cycle to control application and release of the TCC. When the solenoid is commanded off, the TCM senses high voltage. When the solenoid is commanded on, the TCM senses low voltage.

When the TCM detects a continuous short to voltage in the TCC PWM solenoid valve circuit, then DTC P2763 sets, which is a type 'B' DTC.

Conditions for Running the DTC
    • Ignition voltage is between 8.0 and 18.0 volts.
    • Engine is running between 450 and 6,800 RPM at least 5 seconds.
    • HSD2 is commanded ON.

Conditions for Setting the DTC

DTC P02763 sets when the TCM detects a short to voltage in the TCC PWM solenoid valve circuit when the PWM duty cycle is 45% or more.

Action Taken When the DTC Sets
    • The TCM requests the Powertrain Interface Module (PIM) to illuminate the Check Powertrain Malfunction Indicator Lamp (MIL) in the instrument cluster during the second consecutive drive trip in which the 'Conditions for Setting the DTC' are met.
    • 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 freezes the transmission adaptive learning function.
    • The TCM stores DTC P2763 into TCM history.
    • The TCM commands the TCC OFF and disables the TCC solenoid.
    • The TCM inhibits fifth gear if the transmission is in Hot Mode.

Conditions for Clearing the MIL/DTC
    • The PIM turns off the Check Powertrain MIL after the sixth consecutive drive trip in which the TCM does not send a Check Powertrain MIL illumination request.
    • Tech 2 can clear the DTC.
    • The TCM clears the DTC from its memory (history DTC) if the vehicle completes 40 warm-up cycles without a non-emission related DTC occurring.
    • The TCM cancels the DTC default actions when the ignition is off long enough to power down the TCM.

Step

Action

Values

Yes

No

Schematic Reference: Automatic Transmission Controls Schematics

For information on testing wiring faults, refer to Wiring Systems.

1

Has the Diagnostic System Check - Automatic Transmission been completed?

--

Go to Step 2

Go to Diagnostic System Check - Automatic Transmission

2
  1. Connect Tech 2 to the DLC.
  2. Ignition ON, engine OFF.
  3. Clear the DTCs.
  4. Use Tech 2 to command the TCC PWM solenoid ON.

Does the solenoid operate?

--

Go to Step 8

Go to Step 3

3
  1. Ignition OFF.
  2. Disconnect the transmission wiring harness connector X121-X1 from transmission 20-way connector.
  3. Ignition ON, engine OFF.
  4. With a test light connected to ground, probe terminal X1-17 of the transmission wiring harness connector X121-X1.

Does the test light illuminate?

--

Go to Step 4

Go to Step 6

4
  1. Ignition OFF.
  2. Using a digital ohmmeter, measure resistance between terminals X1-17 and X1-20 of the transmission 20-way connector, X121a.

Is resistance reading within the specified value?

10.0-11.5 Ω @ 20°C

11.8-13.6 Ω @ 70°C

Go to Step 5

Go to Step 7

5
  1. Disconnect the transmission wiring harness connector A112-T68 from the TCM.
  2. Using a digital voltmeter check the TCC PWM solenoid valve control circuit 418 for short to voltage condition between transmission wiring harness TCM connector A112-T68, terminal X1-4 and transmission wiring harness connector X121-X1, terminal X1-20.

Does check indicate a short to voltage in the wiring?

--

Go to Step 9

Go to Step 8

6
  1. Ignition OFF.
  2. Disconnect the transmission wiring harness connector A112-T68 from the TCM.
  3. Using a digital ohmmeter check the HSD2 circuit 1525 between transmission wiring harness TCM connector A112-T68, terminal X1-8 and the transmission wiring harness connector X121-X1, terminal X1-17 for an open circuit condition.

Did you find an open circuit condition?

--

Repair open in circuit 1525

Go to Step 8

7
  1. Remove transmission fluid pan. Refer to Transmission Fluid Pan and Filter Assembly Removal.
  2. Inspect transmission internal wiring harness for any sign of damage.
  3. Using a digital ohmmeter check the TCC PWM solenoid wiring circuit between transmission 20-way connector X121-X1a, terminal X1-17 and X1-20 for a short to voltage condition.

Did you find and correct the condition?

--

Repair short to voltage condition in circuit

Go to Step 10

8

Replace TCM. Refer to Transmission Control Module Replacement.

Is the replacement complete?

--

Go to Step 11

--

9

Remove and replace transmission internal wiring harness. Refer to Transmission Internal Electrical Harness Replacement.

Is the replacement complete?

--

Go to Step 11

--

10

Remove and replace TCC PWM solenoid valve. Refer to Torque Converter Clutch Solenoid Replacement.

Is the replacement complete?

--

Go to Step 11

--

11
  1. Perform the following operation to verify the repair:
    2. 1.1. Select DTC on the Tech 2.
    1.2. Select 'Clear info'.
  2. Operate the vehicle in the Conditions for Running the DTC.

Has the test run and passed?

--

System OK

Go to Step 2

When all diagnosis and repairs are completed, clear all DTCs and verify correct operation.