2ML70 - Automatic Transmission
DTC P0961-P0963
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 Descriptor
DTC P0961
- Line Pressure Control (PC) Solenoid System Performance
DTC P0962
- Line Pressure Control (PC) Solenoid Control Circuit Low Voltage
DTC P0963
- Line Pressure Control (PC) Solenoid Control Circuit High Voltage
Diagnostic Fault Information
Typical Scan Tool Data
Circuit/System Description
The line pressure control solenoid is part of the control solenoid valve assembly and is not serviced separately. The line pressure control solenoid regulates the transmission fluid line pressure when the engine is running. The transmission control module varies the current to the normally high line pressure control solenoid valve from 0.1 A for maximum line pressure, to 1.1 A for minimum line pressure. This is accomplished by varying the current in order to obtain the desired line pressure in kPa (psi).
Conditions for Running the DTC
* The engine run time is greater than 5 seconds.
* The vehicle speed is less than 200 km/h (124 mph) for 5 seconds.
* The system voltage is 11-18 V.
P0961
DTC P0961 is not failed this ignition.
P0962
DTC P0962 is not failed this ignition.
P0963
DTC P0963 is not failed this ignition.
Conditions for Setting the DTC
P0961
The transmission control module detects an internal electrical performance malfunction of the line pressure control solenoid control circuit and the actual line pressure does not equal the commanded line pressure for 300 milliseconds.
P0962
The transmission control module detects an internal low voltage electrical malfunction of the line pressure control solenoid control circuit for 300 milliseconds.
P0963
The transmission control module detects an internal high voltage electrical malfunction of the line pressure control solenoid control circuit for 300 milliseconds.
Action Taken When the DTC Sets
DTC P0961
* DTC P0961 is a Type B DTC.
* The transmission control module freezes transmission adaptive functions.
DTC P0962
* DTC P0962 is a Type A DTC.
* The transmission control module defaults the transmission to 3rd gear.
* The transmission control module commands maximum line pressure.
* The transmission control module freezes transmission adaptive functions.
DTC P0963
* DTC P0963 is a Type A DTC.
* The transmission control module freezes transmission adaptive functions.
Conditions for Clearing the DTC
* DTC P0961 is a Type B DTC.
* DTCs P0962 and P0963 are Type A DTCs.
Diagnostic Aids
When attempting to set solenoid electrical DTCs, ensure the transmission control module is warmed up and the transmission is operated long enough to ensure a 3°C (37°F) increase in transmission control module temperature. This will place the transmission control module under the optimal conditions to test solenoid electrical DTCs.
Reference Information
Schematic Reference
Automatic Transmission Controls Schematics (2ML70 - Automatic Transmission)
Connector End View Reference
Component Connector End Views (Connector End Views By Name)
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.
Circuit/System Verification
1. Engine ON, verify the transmission fluid temperature is between 50-80°C (122-176°F).
2. Operate the vehicle long enough to verify at least a 3°C (37°F) rise in TCM temperature parameter, then operate the vehicle in Park for 5 seconds.
3. Engine ON, observe the scan tool Line PC Sol. CKT Status parameter. The reading should display OK or Indeterminate.
• If the reading is not within the specified range, replace the Q8 control solenoid valve assembly.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Control Solenoid Valve and Transmission Control Module Assembly Inspection (Control Solenoid Valve and Transmission Control Module Assembly Inspection)for Control Solenoid inspection.
* Control Module References (Control Module References)for Control Solenoid Valve Assembly replacement, programming and setup.