P2764
DTC P2764
Circuit Description
The torque converter clutch pulse width modulated (TCC PWM) solenoid valve is a normally closed solenoid used to control the apply and release of the converter clutch. The transmission control module (TCM) operates the solenoid with a negative duty cycle. When vehicle operating conditions are appropriate to apply the TCC, the TCM immediately increases the duty cycle to approximately 42 percent. The TCM then ramps the duty cycle to approximately 90 percent to achieve full TCC apply pressure. 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.
Conditions for Running the DTC
The engine is running for 5 seconds or more.
Conditions for Setting the DTC
The TCM detects an open or short to ground on the TCC PWM solenoid valve circuit for 4.4 seconds.
Action Taken When the DTC Sets
* The TCM requests the ECM to illuminate the malfunction indicator lamp (MIL) during the second consecutive trip in which the Conditions for Setting the DTC are met.
* The TCM commands maximum line pressure.
* The TCM forces the TCC solenoid OFF.
* The TCM inhibits TCC engagement.
* The TCM inhibits 4th gear when in HOT mode.
* The TCM freezes transmission adaptive functions.
* The ECM records the operating conditions when the Conditions for Setting the DTC are met. The ECM stores this information as Freeze Frame and Failure Records.
* The TCM records the operating conditions when the Conditions for Setting the DTC are met. The TCM stores this information as Failure Records.
* 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 MIL/DTC
* The TCM turns OFF the MIL during the third consecutive trip in which the diagnostic test runs and passes.
* A scan tool can clear the MIL/DTC.
* The TCM clears the DTC from TCM history if the vehicle completes 40 warm-up cycles without an emission related diagnostic fault occurring.
* The TCM cancels the DTC default actions when the ignition switch is OFF long enough in order to power down the TCM.
Diagnostic Aids
Ensure the wiring harness is not stretched too tightly or other components are pressing on the connector body. Also, inspect for proper clearance to any other components and wiring.
Test Description
The numbers below refer to the step numbers on the diagnostic table.
8. This step tests the electrical operation of the solenoid.
9. This step verifies the TCMs ability to command the solenoid.
14. This step verifies that the circuit has the correct resistance.
Step 1 - Step 7:
Step 8 - Step 17:
