B2356

DTC B1826, B1851, B1861, B2356, B2366, or B2376

Circuit Description

The sensor that sets this DTC is attached to the seat directional motor it monitors. It receives a 5-volt reference and low reference from the memory seat module (MSM)/driver position module (DPM). The sensor sends a voltage signal that varies with the movement of the seat through the sensor signal circuit to the MSM/DPM. Then based on this voltage signal, the MSM/DPM determines the position of the seat.

DTC Descriptors

This diagnostic procedure supports the following DTCs:

* DTC B1826 Seat Recline Position Sensor Circuit Range/Performance
* DTC B2356 Seat Front Vertical Position Sensor Circuit Range/Performance
* DTC B2367 Seat Rear Vertical Position Sensor Circuit Range/Performance
* DTC B2376 Seat Assembly Horizontal Position Sensor Range/Performance

Conditions for Running the DTC

* The MSM/DPM must be powered and cannot have B1327 Battery Voltage Low set as a current DTC for this DTC to set.
* This test will run only when the motors are active.

Conditions for Setting the DTC

If the sensor signal received by the MSM/DPM from a motor being driven in a commanded direction changes by more than 10 counts or 0.2 volts in the wrong direction, the MSM/DPM will set this DTC.

Action Taken When the DTC Sets

* Current and history codes are set.
* The MSM/DPM disables the affected motor during memory recall operations.
* The affected motor will respond to manual positioning commands.

Conditions for Clearing the DTC

* The MSM/DPM will clear the DTC as an active DTC, whenever a manual switch is activated and the MSM/DPM senses that the voltage from the sensor signal changes by more than 2 counts or 0.04 volts in the correct direction.
* The MSM/DPM will clear the history DTC after 50 fault-free ignition cycles.

Diagnostic Aids

* The MSM is also known as the DPM for this vehicle.
* All position sensors use common 5-volt reference and low reference circuits.

Test Description

Step 1 - Step 9:

The numbers below refer to the step numbers on the diagnostic table.
2. This step checks the direction in which the volts change as the switch is activated. The voltage should increase for the forward or up position and decrease for the rearward or down position.
4. This step checks the polarity of the seat position sensor wiring.
5. This step checks the polarity of the seat motor wiring.
6. This step checks the polarity of the seat switch wiring.