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B2170 (With Memory)



DTC B1925 or B2170 (With Memory)

Diagnostic Instructions
- Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
- Review Strategy Based Diagnosis for an overview of the diagnostic approach.
- Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC B1925 02
Driver Seat Cushion Heater Sensor Circuit Short to Ground

DTC B1925 05
Driver Seat Cushion Heater Sensor Circuit High Voltage/Open

DTC B2170 02
Passenger Seat Cushion Heater Sensor Circuit Short to Ground

DTC B2170 05
Passenger Seat Cushion Heater Sensor Circuit High Voltage/Open

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 seat memory control module supplies a 5 V reference voltage through the temperature sensor signal circuit and a ground through the low reference circuit to the sensor. The module monitors the voltage of the sensor signal circuit to determine the temperature of the seat. The temperature sensor varies in resistance based on the temperature of the heating element causing the signal voltage to change. Once the seat reaches the set temperature, the module will then cycle the control circuit of the heating elements ON and OFF in order to maintain the desired seat temperature based on the feedback voltage from the sensor.

Conditions for Running the DTC
- DTC B1325 must not be present.
- The seat memory control module must be powered.

Conditions for Setting the DTC

B1925 02 or B2170 02
The temperature sensor voltage drops below 0.6 V for more than 1 second.

B1925 05 or B2170 05
The temperature sensor voltage is greater than 5 V for more than 1 second.

Action Taken When the DTC Sets
The heated seat function for the affected seat 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 ignition is cycled OFF then back to ACCESSORY or RUN.
- The history DTC will clear after 40 consecutive fault-free ignition cycles have occurred.

Reference Information

Schematic Reference
Heated/Cooled Seat Schematics

Connector End View Reference
Component Connector End Views

Description and Operation
Heated/Vented Seat Description and Operation

Electrical Information Reference
- Circuit Testing
- Connector Repairs
- Testing for Intermittent Conditions and Poor Connections
- Wiring Repairs

Scan Tool Reference
Control Module References for scan tool information

Circuit/System Testing

B1925 02 or B1925 05
1. Ignition OFF, disconnect the X2, X3 harness connectors at the K40 Seat Memory Control Module.
2. Test for 800 Ohms-19 kOhms between the signal circuit terminal 16 X2 and the low reference circuit terminal 12 X3.
3. If less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the E14B Seat Heating Element - Driver Cushion.
4. If greater than the specified range, test the signal circuit and low reference circuit for a short to voltage or an open/high resistance. If the circuits test normal, replace the E14B Seat Heating Element - Driver Cushion.
5. Connect the X2, X3 harness connectors at the K40 Seat Memory Control Module and disconnect the harness connector at the E14B Seat Heating Element - Driver Cushion.
6. Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 2 and ground.
7. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K40 Seat Memory Control Module.
8. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K40 Seat Memory Control Module.
9. If all circuits test normal, replace the K40 Seat Memory Control Module.

B2170 02 or B2170 05
1. Ignition OFF, disconnect the X2, X3 harness connectors at the K40 Seat Memory Control Module.
2. Test for 800 Ohms-19 kOhms between the signal circuit terminal 7 X2 and the low reference circuit terminal 1 X3.
3. If less than the specified range, test for a short between the signal and low reference circuits. If the circuits test normal, replace the E14D Seat Heating Element - Passenger Cushion.
4. If greater than the specified range, test the signal circuit and low reference circuit for a short to voltage or an open/high resistance. If the circuits test normal, replace the E14D Seat Heating Element - Passenger Cushion.
5. Connect the X2, X3 harness connectors at the K40 Seat Memory Control Module and disconnect the harness connector at the E14D Seat Heating Element - Passenger Cushion.
6. Ignition ON, test for 4.8-5.2 V between the signal circuit terminal 2 and ground.
7. If less than the specified range, test the signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K40 Seat Memory Control Module.
8. If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the K40 Seat Memory Control Module.
9. If all circuits test normal, replace the K40 Seat Memory Control Module.

Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- Driver Seat Cushion Heater Replacement (8-Way Power)
- Control Module References for seat memory control module replacement, setup, and programming
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