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B1340



DTC B1340

DTC Descriptors
DTC B1340 00
- Device Power 3 Circuit

DTC B1340 0B
- Device Power 3 Circuit Current Above Threshold

DTC B1340 42
- Device Power 3 Circuit Calibration Data is Not Programmed

DTC B1340 4B
- Device Power 3 Circuit Calibration is Out of Range

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Initial Inspection and Diagnostic Overview






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 00

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

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 out of range.

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

* 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.

Circuit/System Testing

DTCs B1340 00 or B1340 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.

* Driver seat lumbar vertical motor
* Passenger seat lumbar vertical motor
* Steering column tilt motor
* Steering column telescope motor

3. Use a scan tool to clear the current and history diagnostic trouble code.
4. Ignition OFF, disconnect the harness connector at the lumbar motor or steering column actuator for which the DTC set.
5. Ignition ON, operate the motor/actuator in both directions then verify that the DTC set.

If the DTC did not set, test or replace the motor/actuator.

6. Ignition OFF, disconnect the appropriate (C1 or C4) harness connector at the memory seat module.
7. Ignition ON, test for 0 volts between each motor/actuator control circuit and ground.

If greater than 0 volts, test the control circuit for a short to voltage.

8. Test for infinite resistance between each control circuit and ground.

If less than infinite resistance, test the control circuit for a short to ground.

9. Test for infinite resistance between the motor/actuator control circuits:

If less than infinite resistance, test for a short between the control circuits.

10. If all circuits test normal, test or replace the memory seat module.

DTCs B1340 42 or B1340 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. Verification Tests

* Lumbar Replacement - Front Seat (w/AL2) Lumbar Replacement - Front Seat (w/AM3)
* Tilt Motor Replacement
* Telescope Actuator Assembly Replacement
* Programming and Relearning for MSM programming and setup. Programming and Relearning