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Automatic Transmission - 5l40-e/5l50-e - DTC p2763 to DTC p2764 Cadillac XLR I

Automatic Trans 1 illustration ~968 words

Scheme 145

Scheme 145: DTC P2763

Circuit Description

The transmission control module (TCM) provides voltage to the torque converter clutch pulse width modulated (TCC PWM) solenoid valve through 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, in order 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 short to voltage in the TCC PWM Solenoid valve circuit, then DTC P2763 sets. DTC P2763 is a type B DTC.

DTC Descriptor

This diagnostic procedure supports the following DTC

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

Conditions for Running the DTC

  1. The engine run time is greater than 5 seconds.
  2. HSD2 is commanded ON.

Conditions for Setting the DTC

DTC P2763 sets when the TCM detects an short to voltage in the TCC PWM solenoid valve circuit when the PWM duty cycle is 45 percent or greater for 4.3 seconds.

Action Taken When the DTC Sets

  1. The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL) during the second consecutive drive trip in which the Conditions for Setting the DTC are met.
  2. The TCM inhibits fifth gear if the transmission is in Hot Mode.
  3. The TCM inhibits the TCC.
  4. The TCM freezes transmission adaptive functions.
  5. 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.
  6. 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.
  7. The TCM stores DTC P2763 in TCM history.

Conditions for Clearing the MIL/DTC

  1. The ECM turns OFF the MIL after the sixth consecutive drive trip in which the TCM does not send a MIL illumination request.
  2. A scan tool can clear the MIL/DTC.
  3. The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an emission related diagnostic fault occurring.
  4. The TCM cancels the default actions when the ignition is OFF long enough in order to power down the TCM.

Test Description

The number below refers to the step number on the diagnostic table.

  1. 2: Listen for a soft rattling sound when the solenoid energizes. Use a stethoscope if necessary.
StepActionValue(s)YesNo
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Install a scan tool. Turn ON the ignition with the engine OFF. IMPORTANT: Before clearing the DTC, use the scan tool in order to record the ECM Freeze Frame and the TCM Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the ECM and the TCM. Using the Clear Info function erases stored DTCs in both the ECM and TCM. Record the DTC Freeze Frame and Failure Records. Clear the DTC. Use the scan tool in order to command the TCC PWM solenoid ON. Does the solenoid operate?Go to Step 8Go to Step 3
3Turn OFF the ignition. Disconnect the AT 20-way inline harness connector. Install the J 45681 jumper harness to the TCM side of the 20-way connector. See Special Tools . Turn ON the ignition with the engine OFF. With the test lamp connected to ground, probe the solenoid supply voltage circuit of the J 45681 . See Special Tools . Does the test lamp illuminate?Go to Step 4Go to Step 6
4Turn OFF the ignition. Install the J 45681 to the transmission side of the 20-way connector. See Special Tools . Using the DMM, measure the resistance between the solenoid supply voltage circuit and the TCC PWM solenoid valve control circuit of the J 45681 . See Special Tools . Refer to Component Resistance . Is the resistance within the specified range?10.0-13.6 ohmGo to Step 5Go to Step 7
5Disconnect the TCM. Test the TCC PWM solenoid valve control circuit and the solenoid supply voltage for an open or a short to voltage. Refer to Testing for a Short to Voltage . Did you find a condition?Go to Step 9Go to Step 8
6Turn OFF the ignition. Disconnect the TCM. Test the solenoid supply voltage circuit and the solenoid valve control circuit from the TCM to the TCC PWM solenoid valve for an open circuit. Refer to Testing for Continuity . Did you find a condition?Go to Step 9Go to Step 8
7Remove the transmission oil pan. Test the solenoid supply voltage circuit from the 20-way connector to the TCC PWM solenoid valve connector for an open or a short to voltage. Refer to Testing for a Short to Voltage . Did you find a condition?Go to Step 10Go to Step 11
8Replace the TCM. Refer to Control Module References for replacement, setup and programming. Is the action complete?Go to Step 12
9Perform the necessary wiring repairs. Refer to Wiring Repairs . Is the action complete?Go to Step 12
10Replace the AT internal transmission wiring harness. Refer to Transmission Internal Electrical Harness Replacement . Is the action complete?Go to Step 12
11Replace the TCC PWM solenoid valve. Refer to Torque Converter Clutch Solenoid Replacement . Is the action complete?Go to Step 12
12Perform the following procedure in order to verify the repair: Select DTC. Select Clear Info. Turn ON the ignition, with the engine OFF. Select Specific DTC. Enter DTC P2763. Has the test run and passed?Go to Step 13Go to Step 2
13With the scan tool, observe the stored information, capture info and DTC info. Does the scan tool display any DTCs that you have not diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
Before clearing the DTC, use the scan tool in order to record the ECM Freeze Frame and the TCM Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the ECM and the TCM. Using the Clear Info function erases stored DTCs in both the ECM and TCM.

DTC P2763

The transmission control module (TCM) provides voltage to the torque converter clutch pulse width modulated (TCC PWM) solenoid valve through 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, in order 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 open or short to ground in the TCC PWM Solenoid valve circuit, then DTC P2764 sets. DTC P2764 is a type B DTC.

This diagnostic procedure supports the following DTC

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

  1. The engine run time is greater than 5 seconds.
  2. HSD2 is commanded ON.

DTC P2764 sets when either of the following conditions occurs for 4.3 seconds

  1. The TCM detects an open in the TCC PWM solenoid valve circuit when the PWM duty cycle is greater than 20 percent.
  2. The TCM detects a short to ground in the TCC PWM solenoid valve circuit when the PWM duty cycle is greater than 20 percent but less than 50 percent.
  1. The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL) during the second consecutive drive trip in which the Conditions for Setting the DTC are met.
  2. The TCM turns off power to all solenoids.
  3. The transmission will operate in fifth gear if the vehicle has successfully completed a 1-2 upshift in the current ignition cycle. If the vehicle has not completed a 1-2 upshift in the current ignition cycle, the transmission will operate in fourth gear.
  4. The TCM commands maximum line pressure.
  5. The TCM freezes transmission adaptive functions.
  6. Torque management is inhibited.
  7. 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.
  8. 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.
  9. The TCM stores DTC P2764 in TCM history.
  1. The ECM turns OFF the MIL after the sixth consecutive drive trip in which the TCM does not send a MIL illumination request.
  2. A scan tool can clear the MIL/DTC.
  3. The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an emission related diagnostic fault occurring.
  4. The TCM cancels the default actions when the ignition is OFF long enough in order to power down the TCM.

The number below refers to the step number on the diagnostic table.

  1. 2: Listen for a soft rattling sound when the solenoid energizes. Use a stethoscope if necessary.
StepActionValue(s)YesNo
1Did you perform the Diagnostic System Check - Vehicle?Go to Step 2Go to Diagnostic System Check - Vehicle
2Install a scan tool. Turn ON the ignition with the engine OFF. IMPORTANT: Before clearing the DTC, use the scan tool in order to record the ECM Freeze Frame and the TCM Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the ECM and the TCM. Using the Clear Info function erases stored DTCs in both the ECM and TCM. Record the DTC Freeze Frame and Failure Records. Clear the DTC. Use the scan tool in order to command the TCC PWM solenoid ON. Does the solenoid operate?Go to Step 9Go to Step 3
3Turn OFF the ignition. Disconnect the AT 20-way inline harness connector. Install the J 45681 jumper harness to the TCM side of the 20-way connector. See Special Tools . Turn ON the ignition with the engine OFF. With the test lamp connected to ground, probe the solenoid supply voltage circuit of J 45681 . See Special Tools . Does the test lamp illuminate?Go to Step 4Go to Step 7
4Turn OFF the ignition. Install the J 45681 to the transmission side of the 20-way connector. See Special Tools . Using the DMM, measure the resistance between the solenoid supply voltage circuit and the TCC PWM solenoid valve control circuit of the J 45681 . See Special Tools . Refer to Component Resistance . Is the resistance within the specified range?10.0-13.6 ohmGo to Step 5Go to Step 8
5Using the DMM, measure the resistance between the solenoid supply voltage circuit of the J 45681 and ground. See Special Tools . Is the resistance greater than the specified value?50K ohmGo to Step 6Go to Step 8
6Disconnect the TCM. Test the TCC PWM solenoid valve control circuit for the following conditions: Open circuit Short to ground Refer to Testing for Continuity and Testing for Short to Ground . Did you find a condition?Go to Step 10Go to Step 9
7Turn OFF the ignition. Disconnect the TCM. Test the solenoid supply voltage circuit and the solenoid valve control circuit from the TCM to the TCC PWM solenoid valve for an open circuit. Refer to Testing for Continuity . Did you find a condition?Go to Step 10Go to Step 9
8Remove the transmission oil pan. Test the solenoid supply voltage circuit and the solenoid valve control circuit from the 20-way connector to the TCC PWM solenoid valve connector for the following conditions: Open circuit Short to ground Refer to Testing for Continuity and Testing for Short to Ground . Did you find a condition?Go to Step 11Go to Step 12
9Replace the TCM. Refer to Control Module References for replacement, setup and programming. Is the action complete?Go to Step 13
10Perform the necessary wiring repairs. Refer to Wiring Repairs . Is the action complete?Go to Step 13
11Replace the AT internal transmission wiring harness. Refer to Transmission Internal Electrical Harness Replacement . Is the action complete?Go to Step 13
12Replace the TCC PWM solenoid valve. Refer to Torque Converter Clutch Solenoid Replacement . Is the action complete?Go to Step 13
13Perform the following procedure in order to verify the repair: Select DTC. Select Clear Info. Turn ON the ignition, with the engine OFF. Select Specific DTC. Enter DTC P2764. Has the test run and passed?Go to Step 14Go to Step 2
14With the scan tool, observe the stored information, capture info and DTC info. Does the scan tool display any DTCs that you have not diagnosed?Go to Diagnostic Trouble Code (DTC) List - VehicleSystem OK
IMPORTANT
Before clearing the DTC, use the scan tool in order to record the ECM Freeze Frame and the TCM Failure Records. Using the Clear Info function erases the Freeze Frame and Failure Records from the ECM and the TCM. Using the Clear Info function erases stored DTCs in both the ECM and TCM.

DTC P2764