Seat System Diagnosis
DTC B1395
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
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) 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.
Circuit/System Testing
1. Ignition OFF, disconnect the (C2) harness connector at the driver seat adjuster motor assembly.
2. Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal 6 and ground.
• If less than 4.8 volts, test the 5-volt reference circuit to all position sensors for a short to ground or an open. If the circuit tests normal, replace the memory seat module.
• If greater than 5.2 volts, test the following circuits for a short to voltage. If all circuits test normal, replace the memory seat module.
* 5 volt reference circuit
* Each seat, lumbar, and tilt/telescoping steering column position sensor signal circuit
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests
* Front Seat Adjuster Replacement
* Lumbar Replacement - Front Seat (w/AL2) Lumbar Replacement - Front Seat (w/AM3)
* Power Recliner Sensor Replacement - Front
* Tilt Motor Replacement
* Telescope Actuator Assembly Replacement
* Programming and Relearning for MSM setup, and programming. Programming and Relearning