B2170

DTC B1925 or B2170

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 B1925 02
- Left Seat Heater Cushion Sensor Circuit Shorted to Ground

DTC B2170 02
- Right Seat Heater Cushion Sensor Circuit Shorted to Ground




Diagnostic Fault Information






Circuit/System Description

The heated seat temperature sensor that set this diagnostic trouble code (DTC) is located in the seat cushion just under the seat cover with the seat heating element. The temperature sensor is a 2 wire thermistor and resistance through the sensor varies with temperature. The signal circuit is referenced from 5 volts within the module and the temperature of the seat surface determines the signal circuit voltage. Once the seat reaches the set temperature, the module will then cycle the control circuits of the heating elements ON and OFF in order to maintain the desired seat temperature based on the feedback voltage from the sensors.


Conditions for Running the DTC

The memory seat module or rear heated seat module must be powered.


Conditions for Setting the DTC

The temperature sensor voltage drops below 0.80 volt for more than 1 second.


Action Taken When the DTC Sets

The heated seat cushion function for the affected seat will be disabled.


Conditions for Clearing the DTC

* The current DTC will clear 3 seconds after the reference voltage returns to normal operating range, and the ignition is cycled OFF then back to ACC or RUN.
* A history DTC will clear after 50 ignition cycles or with a scan tool using the clear DTCs function.



Reference Information
Schematic Reference

Heated/Cooled Seat Schematics ([1][2]Electrical Diagrams)
Connector End View Reference

Component Connector End Views (Component Connector End Views)
Description and Operation

Heated Seats Description and Operation (KA1) (Heated Seats Description and Operation (KA1))Heated Seats Description and Operation (KA6) (Heated Seats Description and Operation (KA6))
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 MSM or rear heated seat module harness connector X5 for driver or front passenger seat or X4 for a rear passenger seat.
2. Test for a minimum of 850 ohms of resistance from the signal circuit to ground.

• If less than 850 ohms, test the signal circuit for a short to ground. If the circuit tests normal, replace the seat cushion heater element.

3. If all circuits test normal, replace the MSM or rear heated seat module.



Repair Instructions

Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.

* Driver Seat and Passenger Seat Cushion Heater Replacement (Driver Seat and Passenger Seat Cushion Heater Replacement)
* Rear Seat Cushion Heater Replacement (Rear Seat Cushion Heater Replacement)
* Programming and Relearning (Programming and Relearning)for the MSM and rear heated seat module replacement, setup, and programming