For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptors

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

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Line PC Solenoid Control | P0962 | P0963 | P0963 | P0961

### Circuit/System Description

The line pressure control (PC) solenoid is part of the control solenoid (w/body and TCM) valve assembly. The control solenoid (w/body and TCM) valve assembly has no seviceable parts. The TCM varies the current to the normally high line PC solenoid valve from 0.1 amp for maximum line pressure, to 1.1 amps for minimum line pressure. This allows the PC solenoid to regulate the transmission fluid line pressure.

### Conditions for Running the DTC

#### P0961

• | The engine run time is greater than 12 seconds.

• | The ignition voltage is between 9.0 volts and 19.0 volts.

• | The line PC solenoid is commanded ON.

• | DTC P0961 has not failed this ignition cycle.

#### P0962

• | The engine run time is greater than 5 seconds.

• | The ignition voltage is between 9.0 volts and 19.0 volts.

• | The line PC solenoid is commanded ON.

• | DTC P0962 has not failed this ignition cycle.

#### P0963

• | The engine run time is greater than 5 seconds.

• | The ignition voltage is between 9.0 volts and 19.0 volts.

• | The line PC solenoid is commanded ON.

• | DTC P0963 has not failed this ignition cycle.

### Conditions for Setting the DTC

#### P0961

The TCM detects an internal electrical performance malfunction of the line PC solenoid control circuit where the actual line pressure does not equal the commanded line pressure for 10.5 seconds.

#### P0962

The TCM detects an internal low voltage electrical malfunction of the line PC solenoid control circuit for 300 milliseconds.

#### P0963

The TCM detects an internal high voltage electrical malfunction of the line PC solenoid control circuit for 300 milliseconds.

### Action Taken When the DTC Sets

#### P0961, P0963

• | DTCs P0961 and P0963 are Type C DTCs.

• | The TCM freezes transmission adaptive functions.

#### P0962

• | DTC P0962 is a Type A DTC.

• | The TCM defaults the transmission to 3rd gear if the current gear is 1st, 2nd, or 3rd, or 5th gear if the current gear if 4th, 5th, or 6th gear.

• | The TCM inhibits the torque converter clutch (TCC).

• | The TCM commands maximum line pressure.

• | The TCM freezes transmission adaptive functions.

### Conditions for Clearing the DIC/DTC

• | DTCs P0961 and P0963 are Type C DTCs.

• | DTC P0962 is a Type A DTC.

### Reference Information

#### Schematic Reference

Automatic Transmission Controls Schematics

#### Description and Operation

• | Transmission General Description

• | Transmission Component and System Description

• | Electronic Component Description

#### DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

1. Ensure the transmission fluid temperature is between 50-80°C (122-176°F).
2. Perform the Control Solenoid Valve and Transmission Control Module Assembly Cleaning procedure to dislodge debris and free up valves.
3. Operate the vehicle in 2nd gear long enough to ensure at least a 3°C (5°F) rise in TCM temperature, then operate the vehicle in Park for 5 seconds.
4. Verify that the scan tool data parameter, Line PC Sol. CKT Status, displays OK.

⇒ | If not the specified value, replace the control solenoid (w/body and TCM) valve assembly.

5. 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.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

| Important: Before replacing the TCM, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection.

• | Refer to Control Module References for control solenoid (w/body and TCM) valve assembly replacement, setup, and programming.

• | Perform the Service Fast Learn Adapts following all transmission related repairs.

• | Perform the Control Solenoid Valve and Transmission Control Module Assembly Cleaning procedure.