6L50/6L80/6L90 - Automatic Transmission
DTC P2762, P2763, or P2764
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions)provides an overview of each diagnostic category.
DTC Descriptors
DTC P2762
- Torque Converter Clutch (TCC) Pressure Control Solenoid System Performance
DTC P2763
- Torque Converter Clutch (TCC) Pressure Control Solenoid Control Circuit High Voltage
DTC P2764
- Torque Converter Clutch (TCC) Pressure Control Solenoid Control Circuit Low Voltage
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The torque converter clutch (TCC) pressure control solenoid is part of the control solenoid valve assembly which has no serviceable parts. The normally low TCC PC solenoid regulates oil pressure to the TCC regulator valve and TCC control valve. Increasing TCC PC solenoid oil pressure increases oil pressure to the torque converter to apply the clutch. The TCM varies the current to the TCC PC solenoid through a low side driver. Increasing current to the TCC PC solenoid increase oil pressure by closing OFF the solenoid exhaust port. Decreasing current to the TCC PC solenoid decreases oil pressure by opening up the solenoid exhaust port. The TCC PC solenoid power is supplied by the TCM through a high side driver (HSD). The HSD protects the circuit and components from excessive current flow. If excessive current flow is detected, the HSD will turn OFF. When the fault is corrected, the HSD will reset.
Conditions for Running the DTC
P2762
* DTC P2762 has not set this ignition cycle.
* The engine speed is 400 RPM or greater for 5 seconds.
* The ignition voltage is 8.6 volts or greater.
P2763
* DTCs P2763, P0658, or P0659 have not set this ignition cycle.
* The engine speed is 400 RPM or greater for 5 seconds.
* The ignition voltage is 8.6 volts or greater.
* The high side driver is enabled.
P2764
* DTC P2764, P0658, or P0659 has not set this ignition cycle.
* The engine speed is 400 RPM or greater for 5 seconds.
* The ignition voltage is 8.6 volts or greater.
* The high side driver is enabled.
Conditions for Setting the DTC
P2762
The TCM detects an internal electrical performance malfunction of the TCC PC solenoid control circuit where the measured TCC PC solenoid current does not equal the commanded TCC PC solenoid for 5 seconds.
P2763
The TCM detects an open/high resistance or short to voltage on the TCC pressure solenoid control circuit for 5 seconds.
P2764
The TCM detects a short to ground on the TCC pressure solenoid control circuit for 1 minute.
Action Taken When the DTC Sets
P2762
DTC P2762 is a Type C DTC.
P2763
* DTC P2763 is a Type B DTC.
* The TCM inhibits TCC.
* The TCM commands maximum line pressure.
* The TCM freezes transmission adaptive functions.
* The TCM enables Torque management.
* The TCM inhibits TAP Up/Down function.
* The TCM inhibits manual shifting of forward gears.
P2764
* DTC P2764 is a Type A DTC.
* The TCM turns off the high side driver.
* The TCM inhibits TCC.
* The TCM freezes transmission adaptive functions.
* The TCM commands maximum line pressure.
* The TCM inhibits TAP Up/Down function.
* The TCM inhibits Manual Up/Down Shift with the shift selector.
Conditions for Clearing the DIC/DTC
* DTC P2762 is a Type C DTC.
* DTC P2763 is a Type B DTC.
* DTC P2764 is a Type A DTC.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics (6L45/6L50/6L80/6L90 - Automatic Transmission)
Connector End View Reference
* Component Connector End Views (Connector End Views By Name)
* Inline Harness Connector End Views (Connector End Views By Number)
Description and Operation
* Transmission General Description (Transmission General Description)
* Transmission Component and System Description (Transmission Component and System Description)
* Electronic Component Description (Electronic Component Description)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing for Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Powertrain Diagnostic Trouble Code (DTC) Type Definitions)
Scan Tool Reference
Control Module References (Control Module References)for scan tool information
Special Tools
DT-47825-10 - Jumper Harness
Circuit/System Verification
1. Operate the vehicle in 2nd gear long enough to ensure at least a 3°C (5°F) rise in TCM temperature.
2. Operate the vehicle in drive range and ensure TCC is commanded ON for 1 minute. Verify with a scan tool the following test status parameters display OK:
* TCC Pressure Control Solenoid Valve Performance Test Status
* TCC Pressure Control Solenoid Valve Control Circuit High Voltage Test Status
* TCC Pressure Control Solenoid Valve Control Circuit Low Voltage Test Status
3. Operate the vehicle within the Conditions for Running the DTC to verify the DTC does not reset. You may also operate the vehicle within the conditions that you observed from the Freeze Frame/Failure Records data.
Circuit/System Testing
Note: You must perform the Circuit/System Verification first.
1. Ignition OFF, remove the Q8 control solenoid valve assembly. Refer to Control Solenoid Valve and Transmission Control Module Assembly Replacement (6L45/6L50/6L80/6L90 - Automatic Transmission).
2. Perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection (Control Solenoid Valve and Transmission Control Module Assembly Inspection).
3. Place the Q8 control solenoid valve assembly on a clean work surface near the transmission assembly.
4. Connect DT-47825-10 - jumper harness between the vehicle wire harness electrical connector, and the Q8 control solenoid valve assembly electrical connector.
5. Ignition ON, verify with a scan tool the following test status parameters display OK:
* TCC Pressure Control Solenoid Valve Performance Test Status
* TCC Pressure Control Solenoid Valve Control Circuit High Voltage Test Status
* TCC Pressure Control Solenoid Valve Control Circuit Low Voltage Test Status
• If any test status parameter displays Fault or Malfunction, replace the Q8 control solenoid valve assembly.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Perform the Service Fast Learn Adapts (6L45/6L50/6L80/6L90 - Automatic Transmission) following all transmission related repairs.
* Control Module References (Control Module References)for control solenoid valve assembly replacement, setup, and programming.