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
Line PC Solenoid High Side Driver 2 | P1833 | P1833 | P1834 | P0961

### Typical Scan Tool Data

#### Line PC Solenoid

Circuit | Short to Ground | Open | Short to Voltage
--- | --- | --- | ---
Operating Conditions: Engine running, normal operating temperature Parameter Normal Range: OK
Line PC Sol. CKT Status | Short to Ground | Open/Short to Voltage | Open/Short to Voltage
High Side Driver 2 CKT Status | Open/Short to GND | Open/Short to GND | Short to 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. This is accomplished by varying the desired line pressure in kPa (psi).

### Conditions for Running the DTC

#### P0961, P0963

• | Start the ignition switch, run the engine.

• | The line PC solenoid valve is enabled.

#### P0962

• | DTC P0962 is not set.

• | Start the ignition switch, run the engine.

• | The line PC solenoid valve is enabled.

### Conditions for Setting the DTC

#### P0961

The TCM detects an internal electrical performance malfunction of the line PC solenoid control circuit and the actual line pressure does not equal the commanded line pressure for 4.4 seconds in the 5 seconds sample time.

#### P0962

The TCM detects an internal low voltage electrical malfunction of the line PC solenoid control circuit for 300 milliseconds in the 375 milliseconds sample time.

#### P0963

The TCM detects an internal high voltage electrical malfunction of the line PC solenoid control circuit for 300 milliseconds in the 375 milliseconds sample time.

### Action Taken When the DTC Sets

#### 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 is 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.

#### P0961 or P0963

• | DTCs P0961 and P0963 are Type C DTCs.

• | 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.

### Diagnostic Aids

When attempting to set DTCs, ensure the TCM is warmed up and the transmission is operated in 2nd gear long enough to ensure a 3°C (5°F) increase in TCM substrate temperature. This will place the TCM under the optimal conditions to test DTCs.

### Reference Information

#### Schematic Reference

Automatic Transmission Controls Schematics

#### Connector End View Reference

Component Connector End Views

#### DTC Type Reference

• | Diagnostic Trouble Code (DTC) Type Definitions

• | Diagnostic Trouble Code (DTC) List/Type

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

• | Scan Tool Output Controls

• | Scan Tool Data List

• | Scan Tool Data Definitions

### Circuit/System Testing

1. Ensure the transmission fluid temperature is between 50-80°C (122-176°F).
2. 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.
3. Observe the scan tool data parameter Line PC Sol. CKT Status, the parameter should display OK.

⇒ | If the parameter displays Open, Short to Volts, Short to GND or if the DTC resets, perform the Control Solenoid Valve and Transmission Control Module Assembly Inspection.

⇒ | If no concerns are found during the inspection, replace the control solenoid (w/body and TCM) valve assembly.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Service Fast Learn Adapts

• | Control Module References for TCM replacement, setup, and programming