B1340
DTC B1340
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Diagnostic System Check - Vehicle) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Strategy Based Diagnosis) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Diagnostic Procedure Instructions) 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 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
* 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)
* Passenger Seat Schematics (Passenger Seat Schematics)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
Memory Seats Description and Operation (Memory Seats)
Electrical Information Reference
* Circuit Testing (Circuit Testing)
* Connector Repairs (Connector Repairs)
* Testing for Intermittent Conditions and Poor Connections (Testing For Intermittent Conditions and Poor Connections)
* Wiring Repairs (Wiring Repairs)
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.
* 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 (Verification Tests) after completing the diagnostic procedure.
* Driver or Passenger Seat Lumbar Support Replacement (w/AL2) (Driver or Passenger Seat Lumbar Support Replacement (W/AL2))Driver or Passenger Seat Lumbar Support Replacement (w/AM3) (Driver or Passenger Seat Lumbar Support Replacement (W/AM3))
* Tilt Motor Replacement (Service and Repair)
* Steering Column Telescope Actuator Replacement (Steering Column Telescope Actuator Replacement)
* Control Module References (Programming and Relearning) for MSM replacement, programming and setup