B2170

DTC B2170

DTC DESCRIPTORS
This diagnostic procedure supports the following DTCs:
DTC B1925 02: Left Seat Heater Cushion Sensor Circuit Shorted to Ground
DTC B1925 05: Left Seat Heater Cushion Sensor Circuit Shorted to Battery or Open
DTC B2170 02: Right Seat Heater Cushion Sensor Circuit Shorted to Ground
DTC B2170 05: Right Seat Heater Cushion Sensor Circuit Shorted to Battery or Open




DIAGNOSTIC FAULT INFORMATION

IMPORTANT: Always perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Testing and Inspection

CIRCUIT/SYSTEM DESCRIPTION
The heated seat temperature sensor that set this diagnostic trouble code (DTC) is located in either the seat cushion or seat back just under the seat cover with the seat heating element. The heated seat module supplies a separate 5-volt reference voltage through the temperature sensor signal circuit and a ground through the low reference circuit to the seat temperature sensors. The module monitors the voltage of the sensor signal circuits 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 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 heated seat module is active, and none of the power diagnostic DTCs are current.

CONDITIONS FOR SETTING THE DTC
The following conditions exist for more than 1 second:
B1925/B2170 02: The temperature sensor voltage drops below 0.80 volt for more than 1 second.
B1925/B2170 05: The temperature sensor voltage exceeds 5 volts 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 3 seconds after the reference voltage returns to normal operating range.
- The history DTC will clear after 50 consecutive fault-free ignition cycles have occurred.

CIRCUIT/SYSTEM TESTING
1. Ignition OFF, disconnect the heated seat module harness connectors C2 and C4.
2. Test for 850-12.0K ohms of resistance between the signal circuit and the low reference circuit of the seat cushion temperature sensor.
- If greater than 12.0K ohms, test the signal circuit and low reference circuit for a short to voltage or an open/high resistance. If the circuits/connections test normal, replace the heated seat cushion temperature sensor/heating element.
- If less than 850 ohms, test the signal circuit for a short to ground. If the circuit/connections test normal, replace the heated seat cushion temperature sensor/heating element.
3. If all circuits/connections test normal, replace the heated seat module.

REPAIR INSTRUCTION

IMPORTANT: Always perform the Diagnostic Repair Verification after completing the diagnostic procedure.
- Seat Cushion Trim Cover and Pad Replacement
- Control Module References for the rear heated seat module replacement, setup, and programming