GM Service Manual Online
For 1990-2009 cars only

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 B1335 00: Device Power 3 Circuit

DTC B1335 0B: Device Power 3 Circuit Current Above Threshold

DTC B1335 42: Device Power 3 Circuit Calibration Data Set Not Programed

DTC B1335 4B: Device Power 3 Circuit Calibration Not Learned

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Driver Seat Front Vertical Motor Down Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Driver Seat Front Vertical Motor Up Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Driver Seat Rear Vertical Motor Down Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Driver Seat Rear Vertical Motor Up Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Driver Seat Horizontal Motor Forward Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Driver Seat Horizontal Motor Rearward Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Driver Seat Recline Motor Forward Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Driver Seat Recline Motor Rearward Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Driver Seat Lumbar Motor Up Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Driver Seat Lumbar Motor Down Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Driver Seat Lumbar Motor Forward Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Driver Seat Lumbar Motor Rearward Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Adjustable Pedal Motor Forward Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

Adjustable Pedal Motor Rearward Control

B3920 02

1

B3920 01

B1335 00 B1335 0B

1. Power seat motor inoperative

Circuit/System Description

The memory seat module (MSM) monitors the current supplied to the seat adjuster motors. The MSM can detect both absolute and differential current levels from the seat motors. Absolute current is the maximum allowable current the module will supply to the motors. A differential current mismatch occurs when the current supplied to the seat motors does not match the current returning from the motors.

Conditions for Running the DTC

The MSM establishes that it is not closing to a shorted motor control circuit before the motors are active.

Conditions for Setting the DTC

The following conditions exist for more than 1 second:

B1335 00

Current out of the module does not match the current returning to the module within 5 amps.

B1335 0B

The absolute current or an over-current has exceeded the maximum value allowed.

B1335 42

This DTC will set if the module calibration is not programmed.

B1335 4B

This DTC will set if the module calibration is out of range.

Action Taken When the DTC Sets

The adjustable pedal motor and all driver seat adjuster motors are disabled.

Conditions for Clearing the DTC

    • The current DTC will clear and set the code to history, 3 seconds after no motor movement is requested or the current is no longer mismatched, and the ignition is cycled OFF then back to ACC or RUN.
    • A history DTC will clear after 50 ignition cycles or with a scan tool using the clear DTCs function.

Reference Information

Schematic Reference

    •  Driver Seat Schematics
    •  Passenger Seat Schematics
    •  Adjustable Pedal Schematics

Connector End View Reference

    •  Power Seat Connector End Views
    •  Adjustable Pedal Connector End Views

Electrical Information Reference

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

DTC Type Reference

DTC Symptom Description

Scan Tool Reference

    •  Scan Tool Data List
    •  Scan Tool Data Definitions

Module Internal Malfunction

If DTCs  B1335 42 or B1335 4B are set history or current, the only option is module replacement.

Circuit/System Testing

  1. Use a scan tool to clear the current and history diagnostic trouble code.
  2. Ignition ON, while observing the scan tool for DTCs, operate the seat adjuster switch in both directions for each directional motor.
  3. Disconnect the suspect seat motor for which the DTC set.
  4. Clear the current and history diagnostic trouble code.
  5. While observing the scan tool for DTCs, operate the suspect seat motor adjuster switch in both directions.
  6. If the DTC set current or history, test the motor control circuits for a short to ground, or an open/high resistance. If the circuits test normal, replace the memory seat module.
  7. If all circuits/connections test normal, replace the seat motor.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

    •  Front Seat Recliner Actuator Motor Replacement
    •  Front Seat Lumbar Support Replacement
    •  Front Seat Adjuster Replacement
    •  Brake Pedal Assembly Replacement
    •  Control Module References for MSM replacement, setup, and programming