B2170

DTC B2170

DTC DESCRIPTOR
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 prior to using this diagnostic procedure.

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 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 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 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
B1925/B2170 02: The temperature sensor voltage drops below 0.80 volts 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 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 temperature sensor.
- If less than 850 ohms, test the signal circuit for a short to ground. If the circuit/connections test normal, replace the heated seat temperature sensor.
3. If all circuits/connections circuits test normal, replace the heated seat module.

REPAIR INSTRUCTIONS

IMPORTANT: Always perform the Diagnostic repair varification after completing the diagnostic procedure.

- Seat Cushion Heater Element Replacement - Front (Impala) Seat Cushion Heater Element Replacement - Front (Monte Carlo)
- Control Module References for Heated Seat Control Module Replacement-Front.