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B1340




DTC B1340

Diagnostic Instructions

* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.

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/System Description

The memory seat module (MSM) monitors the current supplied to both steering column motors. 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 steering column motors 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 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 (Driver Seat Schematics)
* Tilt/Telescoping Steering Column Schematics (Tilt/Telescoping Steering Column Schematics)

Connector End View Reference

Component Connector End Views (Connector Views)
Description and Operation

Memory Seats Description and Operation (Memory Seats Description and Operation)
Electrical Information Reference

* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

Scan Tool Reference

Control Module References (Programming and Relearning) 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.

* Steering Column Tilt motor
* Steering Column Telescope motor

3. Clear the diagnostic trouble codes.
4. Ignition OFF, disconnect the harness connector at the appropriate 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.

* 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 steering column.

* 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.

Component Testing

Seat Motor
1. Ignition OFF, disconnect the harness connector at the appropriate seat motor.

Important: When performing the following tests, make sure that the seat is not already in the position the test is attempting to produce.


2. Install a 30 A fused jumper wire between the control terminal 1 and 12 volts. Momentarily install a jumper wire between the control terminal 5 and ground. The seat motor should momentarily perform the appropriate FORWARD/REARWARD/UP/DOWN function.

If the function does not perform as specified, replace the seat motor.

3. Reverse the polarity of jumper wires. The a seat motor should perform in the opposite direction.

If the function does not perform as specified, replace the seat motor.

Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Steering Column Tilt Wheel Actuator Motor Replacement (Service and Repair)
* Steering Column Telescope Actuator Motor Replacement (Service and Repair)
* Control Module References (Programming and Relearning) for MSM replacement, programming and setup