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

### Circuit/System Description

The line pressure control (PC) solenoid is part of the control solenoid (w/body and TCM) valve assembly and is not serviced separately. The line PC solenoid regulates the transmission fluid line pressure. 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.

### Conditions for Running the DTC

• | The engine speed is greater than 500 RPM for 5 seconds.

• | The ignition voltage is between 8.6 volts and 19.0 volts.

• | The line PC solenoid is commanded ON.

### Conditions for Setting the DTC

#### P0961

The TCM detects an invalid voltage in the line PC solenoid control circuit for 4.4 seconds in a 5.0 second sample.

#### P0962

The TCM detects low voltage on the line PC solenoid control circuit for 300 milliseconds in a 375 millisecond sample.

#### P0963

The TCM detects high voltage on the line PC solenoid control circuit for 300 milliseconds in a 375 millisecond sample.

### Action Taken When the DTC Sets

#### P0961

• | DTC P0961 is a Type C DTC.

• | 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.

#### P0963

• | DTC P0963 is a Type C DTC.

• | The TCM freezes transmission adaptive functions.

• | The TCM commands maximum line pressure.

### Conditions for Clearing the DIC/DTC

• | DTCs P0961 and P0963 are Type C DTCs.

• | DTC P0962 is a Type A DTC.

### Reference Information

#### Description and Operation

Transmission General 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 to dislodge debris and free up the 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. 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.

⇒ | If the DTC does reset, replace the control solenoid (w/body and TCM) valve assembly.

### Repair Instructions

Important:

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

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

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Control Solenoid Valve and Transmission Control Module Assembly Cleaning

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