B0169

DTC B0169

CIRCUIT DESCRIPTION
The auxiliary inside air temperature sensor assembly allows the auxiliary HVAC control module to monitor the temperature of the air inside the passenger compartment. The module applies 5 volts to internal input resistor that is connected to the signal circuit of the air temperature sensor. The module provides ground to the air temperature sensor through the low reference circuit. The auxiliary HVAC control module monitors the voltage drop across the air temperature sensor and uses the input for automatic control calculations. When the air temperature is cold, the resistance of the sensor is high and the voltage signal is high. When the air temperature is hot, the resistances of the sensor is low and the voltage signal is low.

CONDITIONS FOR RUNNING THE DTC
- Battery voltage to the auxiliary HVAC control module is greater than 8.7V and less than 16.5V.
- The ignition is turned ON.

CONDITIONS FOR SETTING THE DTC
The auxiliary HVAC control module determines that the voltage applied to the input for the auxiliary inside air temperature sensor is less than 0.09V or greater than 4.9V.

ACTION TAKEN WHEN THE DTC SETS
The auxiliary HVAC control module use a default value of 128 Counts for the Inside Air Temp. Sensor parameter. This value will not be displayed on the scan tool. The value displayed on the scan tool is the actual value of the signal circuit.

CONDITIONS FOR CLEARING THE DTC
- The DTC will become history if the auxiliary HVAC control module no longer detects the condition that set the DTC.
- The history DTC will clear after 100 fault free ignition cycles.
- The DTC can be cleared with a scan tool.

TEST DESCRIPTION

Steps 1-11:

Step 12:

The numbers below refers to the step numbers on the diagnostic table.
2. Verifies that the temperature displayed is not within the calibrated range.
3. Tests for the proper operation of the circuit in the high voltage range.
4. Tests for the proper operation of the circuit in the low voltage range. If the fuse in the jumper opens when you perform this test, the signal circuit is shorted to voltage.