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 B1340 00: Device Power 4 Circuit
DTC B1340 0B: Device Power 4 Circuit Current Above Threshold
DTC B1340 42: Device Power 4 Circuit Calibration Data Set Not Programmed
DTC B1340 4B: Device Power 4 Circuit Calibration Not Learned

### Diagnostic Fault Information

Circuit | Short to Ground | High Resistance | Open | Short to Voltage | Signal Performance
--- | --- | --- | --- | --- | ---
Driver Seat Lumbar Motor Up Control | B3921 02 | B1340 00, B1340 0B | 1 | B3921 01 | B1340 42, B1340 4B, B1860 5A
Driver Seat Lumbar Motor Down Control | B3921 02 | B1340 00, B1340 0B | 1 | B3921 01 | B1335 42, B1335 4B, B1860 5A
Steering Column Telescope Motor Forward Control | B3921 02 | B1340 00, B1340 0B | 2 | B3921 01 | B1335 42, B1335 4B, B2860 5A
Steering Column Telescope Motor Rearward Control | B3921 02 | B1340 00, B1340 0B | 2 | B3921 01 | B1335 42, B1335 4B, B2860 5A
Steering Column Tilt Motor Down Control | B3921 02 | B1340 00, B1340 0B | 3 | B3921 01 | B1335 42, B1335 4B, B2880 5A
Steering Column Tilt Motor Up Control | B3921 02 | B1340 00, B1340 0B | 3 | B3921 01 | B1335 42, B1335 4B, B2880 5A
1. Lumbar vertical motor is inoperative 2. Steering Column Does Not Telescope In/Out 3. Steering Column Does Not Tilt Up/Down

### Circuit/System Description

The memory seat module (MSM) monitors the current supplied to both steering column motors and the lumbar vertical motor. The MSM can detect both absolute and differential current levels from the these 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 motors does not match the current returning from the motors.

### Conditions for Running the DTC

The lumbar vertical motor or the steering column motors must be active.

### Conditions for Setting the DTC

#### B1340 00

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

#### B1340 0B

The absolute current has exceeded the maximum value allowed.

#### B1340 42

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

#### B1340 4B

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

### Action Taken When the DTC Sets

All movement related to the seat lumbar motor and steering column motors are 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

• | Tilt/Telescoping Steering Column Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Memory Seats Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Testing

#### B1340 00 or B1340 0B

1. Ignition ON, use a scan tool to clear the current and history diagnostic trouble code.
2. Determine which motor set this DTC by operating the motors listed below one at a time in both directions. Check for the DTC to set between each motor test.

• | Driver Seat Lumbar Vertical Motor

• | Steering Column Tilt Motor

• | Steering Column Telescope Motor

3. Clear the diagnostic trouble codes.
4. Ignition OFF, disconnect the harness connector at the appropriate lumbar motor or steering column motor for which the DTC set.
5. Ignition ON, operate the motor adjuster switch in both directions. DTC B1340 00 or B1340 0B should not set.

⇒ | If the DTC sets, test for a short between the appropriate motor control circuits listed below. If the circuits test normal, replace the MSM.

• | Lumbar vertical motor terminal 1 and terminal 5

• | Steering column telescope motor terminal C and terminal D

• | Steering column tilt motor terminal A and terminal B

6. Test the appropriate control circuits listed below for a high resistance. If the circuits test normal, test or replace the appropriate lumbar motor or steering column motor.

• | Lumbar vertical motor terminal 1 and terminal 5

• | Steering column telescope motor terminal C and terminal D

• | Steering column tilt motor terminal A and terminal B

#### B1340 42 or B1340 4B

If either DTC is set, replace the MSM.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Front Seat Lumbar Support Replacement

• | Steering Column Replacement

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