B2356
DTC B1826, B1851, B1861, B2356, B2366, or B2376
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 B1826
- Driver Recline Sensor Performance
DTC B2356
- Driver Front Vertical Sensor Performance
DTC B2366
- Driver Rear Vertical Sensor Performance
DTC B2376
- Driver Seat Assembly Horizontal Sensor Performance
Diagnostic Fault Information
Circuit/System Description
The position sensor that sets this diagnostic trouble code (DTC) is either attached to the seat directional motor drive cable or directly to the motor it monitors. It receives a 5-volt reference and low reference from the memory seat module (MSM). The sensor sends a voltage signal that varies with the movement of the seat through the signal circuit to the MSM. Then based on this voltage signal, the MSM determines the position of the seat.
Conditions for Running the DTC
* DTC B1327 must not be present.
* Battery voltage must be between 9-16 volts.
Conditions for Setting the DTC
This DTC will set, if the MSM is controlling a motor in one direction and it's position sensor is tracking the motor in the opposite direction. The sensor is either mounted or wired incorrectly, or the polarity of the motor control circuits are reversed.
Actions Taken When the DTC Sets
The motor associated with the fault will be disabled for memory functions.
Conditions for Clearing the DTCs
* The condition responsible for setting the DTC no longer exists.
* A history DTC will clear once 50 consecutive malfunction-free ignition cycles have occurred.
Diagnostic Aids
The memory seat module is also referred to as the Driver Position Module in certain scan tool menus.
Reference Information
Schematic Reference
Driver Seat Schematics (Driver 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
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Testing
B1826
1. Ignition OFF, disconnect the X1 harness connector at the driver seat recline motor.
2. Verify that the control circuits listed below are in the correct harness connector cavities:
* Recline forward terminal A
* Recline rearward terminal B
• If the control circuits are not in the correct cavities, make the appropriate changes.
3. Disconnect the X2 harness connector at the driver seat recline motor.
4. Verify that the 5-volt reference and low reference circuits listed below are in the correct harness connector cavities:
* 5-volt reference terminal A
* Low reference terminal D
• If the 5-volt reference and low reference circuits are not in the correct cavities, make the appropriate changes.
5. If all circuits test normal, replace the MSM.
B2356, B2366, B2376
1. Ignition OFF, disconnect the X1 harness connector at the driver seat adjuster motor assembly.
2. Verify that the appropriate control circuits listed below are in the correct harness connector cavities:
* Front vertical motor up control terminal C
* Front vertical motor down control terminal D
* Rear vertical motor up control terminal E
* Rear vertical motor down control terminal F
* Seat horizontal motor forward control terminal A
* Seat horizontal motor rearward control terminal B
• If the control circuits are not in the correct cavities, make the appropriate changes.
3. Disconnect the appropriate X2, X3, X4 harness connector at the driver seat adjuster motor assembly.
4. Verify that the appropriate 5-volt reference and low reference circuits listed below are in the correct harness connector cavities:
* Front vertical sensor 5-volt reference terminal C
* Front vertical sensor low reference terminal A
* Rear vertical sensor 5-volt reference terminal C
* Rear vertical sensor low reference terminal A
* Seat horizontal sensor 5-volt reference terminal A
* Seat horizontal sensor low reference terminal C
• If the 5-volt reference and low reference circuits are not in the correct cavities, make the appropriate changes.
5. If all circuits test normal, replace the MSM.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
Control Module References (Programming and Relearning) for MSM replacement, setup, and programming