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DTC P0961-P0963

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 Solenoid Valve System Performance

DTC P0962: Line Pressure Control Solenoid Valve Control Circuit Low Voltage

DTC P0963: Line Pressure Control Solenoid Valve 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

Typical Scan Tool Data

Line Pressure Control Solenoid Valve Performance Test Status

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Operating Conditions: Engine running, normal operating temperature

Parameter Normal Range: OK

Line Pressure Control Solenoid Valve Control

--

--

--

Fault or Malfunction

Line Pressure Control Solenoid Valve Control Circuit Low Voltage Test Status

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Operating Conditions: Engine running, normal operating temperature

Parameter Normal Range: OK

Line Pressure Control Solenoid Valve Control

Fault or Malfunction

--

--

--

Line Pressure Control Solenoid Valve Control Circuit High Voltage Test Status

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Operating Conditions: Engine running, normal operating temperature

Parameter Normal Range: OK

Line Pressure Control Solenoid Valve Control

-

Fault or Malfunction

Fault or Malfunction

--

Circuit/System Description

The line pressure control (PC) solenoid is part of the control solenoid valve assembly which has no serviceable components. The normally high line PC solenoid regulates and directs the PC solenoid oil pressure to the pressure regulator valve. Increasing line PC solenoid pressure increases transmission line pressure. The transmission control module (TCM) varies the current to the line PC solenoid through a low side driver. Decreasing the current to the line PC solenoid increases line PC solenoid oil pressure by closing OFF the solenoid exhaust port. Increasing the current to the line PC solenoid decreases line PC oil pressure by opening the solenoid exhaust port. Line 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

P0961, P0962, or P0963

    • The engine speed is 400 RPM or greater for 5 seconds.
    • The ignition voltage is 9.0 volts or greater.

Conditions for Setting the DTC

P0961

The TCM detects an internal electrical malfunction of the line PC solenoid where the measured line PC solenoid current does not equal the commanded line PC solenoid current for 5 seconds.

P0962

The TCM detects a short-circuit to ground on the line PC solenoid control circuit for 2 seconds.

P0963

The TCM detects an open circuit or short-circuit to voltage on the line PC solenoid control circuit for 5 seconds.

Action Taken When the DTC Sets

P0961 or P0963

    • DTCs P0961 and P0963 are Type B DTCs.
    • The TCM freezes transmission adaptive functions.
    • The TCM commands maximum line pressure.

P0962

    • DTC P0962 is a Type A DTC.
    • The TCM limits the transmission to 5th gear and reverse.
    • The TCM inhibits the torque converter clutch (TCC).
    • The TCM commands maximum line pressure.
    • The TCM freezes transmission adaptive functions.
    • The TCM turns the high side driver OFF.
    • The TCM inhibits Tap Up/Down function.
    • The TCM inhibits manual shifting of forward gears.
    • The TCM enables torque management.

Conditions for Clearing the DIC/DTC

    • DTCs P0961 and P0963 are Type B DTCs.
    • DTC P0962 is a Type A DTC.

Reference Information

Schematic Reference

Automatic Transmission Controls Schematics

Connector End View Reference

    •  Component Connector End Views
    •  Inline Harness Connector End Views

Description and Operation

    •  Transmission General Description
    •  Transmission Component and System Description
    •  Electronic Component Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References for scan tool information

Special Tools

DT-48616-10 Adapter Harness

For equivalent regional tools, refer to Special Tools .

Circuit/System Verification

  1. Engine running in PARK position. Move the gear shift lever into each gear position and back into PARK position. Verify with a scan tool, the following test status parameters display OK.
  2. • Line Pressure Control Solenoid Valve Performance Test Status
    • Line Pressure Control Solenoid Valve Control Circuit High Voltage Test Status
    • Line Pressure Control Solenoid Valve Control Circuit Low Voltage Test Status
  3. After performing the above steps, verify that the DTC does not reset by operating the vehicle within the Conditions for Running the DTC. You may also operate the vehicle within the conditions you observe from the Freeze Frame/Failure Records data. If the vehicle passes the Circuit/System Verification procedure, then STOP. Do not perform the Circuit/System Testing or Component Testing as this may result in an unnecessary part replacement. Refer to Testing for Intermittent Conditions and Poor Connections .

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 .
  2. Perform the 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-48616-10 harness between the vehicle wire harness X1 14-way transmission 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.
  6. • Line Pressure Control Solenoid Valve Performance Test Status
    • Line Pressure Control Solenoid Valve Control Circuit High Voltage Test Status
    • Line 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 after completing the diagnostic procedure.

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

    • Refer to Control Module References for control solenoid valve assembly replacement, set-up, and programming.
    • Perform the Transmission Adaptive Values Learn following all transmission related repairs.
    • Perform the Control Solenoid Valve and Transmission Control Module Assembly Cleaning procedure.
   


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