Power Seats
DTC B1395
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 B1395 02
- Device Voltage Reference Output Circuit Shorted to Ground
DTC B1395 05
- Device Voltage Reference Output Circuit Shorted to Battery or Open
Diagnostic Fault Information
Circuit/System Description
The memory seat module (MSM) supplies a 5-volt reference voltage to the driver seat position sensors, lumbar position sensors, passenger seat lumbar vertical position sensor, and the steering column position sensors. The MSM monitors this reference voltage to ensure the accuracy of the voltages being returned from the sensors. If the voltage exceeds the normal operating range, errors will occur in the memory recall operations of the seat and steering column.
Conditions for Running the DTC
The MSM must be powered.
Conditions for Setting the DTC
B1395 02
The reference voltage drops below 4.8 volts for more than 300 mS.
B1395 05
The reference voltage exceeds 5.2 volts for more than 300 mS.
Action Taken When the DTC Sets
All memory recall and seat massage functions will be disabled.
Conditions for Clearing the DTC
* The current DTC will clear and set the code to history 3 seconds after the reference voltage returns to normal operating range 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.
* All seat, lumbar, and tilt/telescoping steering column position sensors use common ground and 5-volt reference circuits.
* If the 5-volt reference circuit is shorted to voltage multiple position sensor codes will set.
* If the 5-volt reference circuit is shorted to ground multiple position sensor codes will set.
* A short to voltage on one of the position sensor signal circuits may set this code.
* An internal short to ground in one of the position sensors may set this code.
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 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
Programming and Relearning (Programming and Relearning) for Scan Tool Information
Circuit/System Testing
1. Ignition OFF, disconnect the harness connector for all position sensors connected to the 5-volt reference circuit.
2. Ignition ON, observe all scan tool sensor parameters for Seat 1, Seat 2, and Column Info. The readings should be 0.0 volts.
• If greater than the specified value, test the appropriate signal circuit for a short to voltage. If the circuit tests normal, replace the MSM.
3. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit at any one of the position sensors and ground.
• If less than 4.8 volts, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the MSM.
• If greater than 4.8 volts, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the MSM.
4. Connect each position sensor associated with the 5 volt reference circuit one at a time while monitoring the measured voltage. The voltage reading should remain within the specified range.
• If not within the specified range, replace the position sensor.
5. If all circuits test normal, replace the MSM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* Front Seat Adjuster Replacement (Front Seat Adjuster Replacement)
* Front Seat Lumbar Support Replacement (w/AM3) (Front Seat Lumbar Support Replacement (w/AM3))Front Seat Lumbar Support Replacement (w/AL2) (Front Seat Lumbar Support Replacement (w/AL2))
* Front Seat Recliner Position Sensor Replacement (Service and Repair)
* Tilt Motor Replacement (Service and Repair)
* Telescope Actuator Assembly Replacement (Telescope Actuator Assembly Replacement)
* Programming and Relearning (Programming and Relearning) for MSM replacement, setup, and programming