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 Programmed

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

1. Power seat motor inoperative

Circuit/System Description

The memory seat module (MSM) monitors the current supplied to the driver seat adjuster motors, recline motor and lumbar horizontal motor. It 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 driver seat adjuster motors, recline motor or the lumbar horizontal motor must be active.

Conditions for Setting the DTC

B1335 00

The current out of the module does not match the current returning to the module from 1.5-5.0A.

B1335 0B

The differential current measured through the high and low side of the power rail is within tolerance of each other, but the absolute current or an over-current has exceeded the maximum value.

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

All movement related to the seat cushion and recline motors is aborted.

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 power mode changes to OFF then back to ACC or RUN.
    • The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

Diagnostic Aids

The scan tool may reference the Memory Seat Module (MSM) as the Driver Position Module.

Reference Information

Schematic Reference

    •  Driver Seat Schematics
    •  Passenger Seat Schematics

Connector End View Reference

Power Seat Connector End Views

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

B1335 00 or B1335 0B

  1. Use a scan tool to clear the current and history diagnostic trouble code.
  2. Ignition ON, determine which motor set this DTC by operating the following motors one at a time in both directions. Check for the DTC to set between each motor test.
  3. • Driver seat front vertical motor
    • Driver seat rear vertical motor
    • Driver seat horizontal motor
    • Driver seat recline motor
    • Driver seat lumbar horizontal motor
  4. Use a scan tool to clear the current and history diagnostic trouble code.
  5. Ignition OFF, disconnect the harness connector at the seat or lumbar motor for which the DTC set.
  6. Ignition ON, operate the motor in both directions then verify that the DTC set.
  7. If the DTC did not set, test or replace the motor.
  8. Ignition OFF, disconnect the appropriate C1 or C4 harness connector at the memory seat module.
  9. Ignition ON, test for 0 volt between each motor control circuit and ground.
  10. If greater than 0 volt, test the control circuit for a short to voltage.
  11. Test for infinite resistance between each control circuit and ground.
  12. If less than infinite resistance, test the control circuit for a short to ground.
  13. Test for infinite resistance between the motor control circuits:
  14. If less than infinite resistance, test for a short between the control circuits.
  15. If all circuits test normal, test or replace the memory seat module.

B1335 42 or B1335 4B

If either DTC is set history or current, the only option is module replacement.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

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