Diagnostic Instructions

DTC Descriptors

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 Down Control	B3921 02	B1340 0B	1	B3921 01	B1340 42, B1340 4B, B1860 5A
Driver Seat Lumbar Motor Up Control	B3921 02	B1340 0B	1	B3921 01	B1340 42, B1340 4B, B1860 5A
Passenger Massage Down Motor Control	B3921 02	B1340 0B	2	B3921 01	B1340 0B, B1340 4B
Passenger Massage Up Motor Control	B3921 02	B1340 0B	2	B3921 01	B1340 0B, B1340 4B
Steering Column Telescope Motor Forward Control	B3921 02	B1340 0B	3	B3921 01	B1340 42, B1340 4B, B2860 5A
Steering Column Telescope Motor Rearward Control	B3921 02	B1340 0B	3	B3921 01	B1340 42, B1340 4B, B2860 5A
Steering Column Tilt Motor Down Control	B3921 02	B1340 0B	4	B3921 01	B1340 42, B1340 4B, B2880 5A
Steering Column Tilt Motor Up Control	B3921 02	B1340 0B	4	B3921 01	B1340 42, B1340 4B, B2880 5A
1. Driver seat lumbar vertical motor is inoperative 2. Passenger seat lumbar vertical motor is inoperative 3. Steering column does not telescope in or out 4. Steering column does not tilt up or down

Circuit/System Description

The memory seat module (MSM) monitors the current supplied to driver and passenger seat lumbar vertical motors and both steering column actuators. 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 seat lumbar motors or steering wheel actuators must be active.

Conditions for Setting the DTC

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 motors and steering wheel actuators is aborted.

Conditions for Clearing the DTC

Diagnostic Aids

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

Reference Information

Schematic Reference

Connector End View Reference

Component Connector End Views

Description and Operation

Memory Seats Description and Operation

Electrical Information Reference

Scan Tool Reference

Control Module References for scan tool information

Circuit/System Testing

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

•	Passenger seat lumbar vertical motor

•	Steering column tilt actuator

•	Steering column telescope actuator

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 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.

•	Driver seat lumbar vertical motor terminal A and terminal B

•	Passenger seat lumbar vertical motor terminal A X354 and terminal B X354

•	Steering column tilt actuator terminal A X1 and terminal B X1

•	Steering column telescope actuator terminal A X1 and terminal B X1

⇒	If greater than the specified value, test the control circuit for a short to voltage.

6. Test the appropriate control circuits listed below for a high resistance.

•	Driver seat lumbar vertical motor terminal A and terminal B

•	Passenger seat lumbar vertical motor terminal A X354 and terminal B X354

•	Steering column tilt actuator terminal A X1 and terminal B X1

•	Steering column telescope actuator terminal A X1 and terminal B X1

7. If the circuits test normal, test or replace the appropriate lumbar motor or steering column motor.

B1340 42 or B1340 4B

If either DTC is set history or current, replace the MSM.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.