DTC 013

Diagnostic Trouble Code Chart:

Wiring Schematics:

CIRCUIT DESCRIPTION
The Inside Air Temperature Sensor is a thermistor that controls signal voltage to the HVAC programmer. The inside air temperature sensor contains an electric fan which pulls the air from the passenger compartment to the sensor. The HVAC programmer supplies voltage on circuit 734. When the sensor is cold, the resistance is high and the HVAC programmer will sense a high signal voltage at terminal F7 (Buick, Oldsmobile) or terminal D7 (Pontiac). When the sensor warms, resistance is reduced and the signal voltage is pulled low through circuit 1704. Signal voltage will vary from 5 V (open circuit) to 0 V (short circuit).

CONDITIONS FOR SETTING THE DTC
^ The ignition is ON.
^ DTC 010 is not set.
^ Circuit short or open.

ACTION TAKEN WHEN THE DTC SETS
^ A default value of 24°C (75°F) will be used by the HVAC programmer.
^ The default value allows the system to operate.

CONDITIONS FOR CLEARING THE DTC
^ Using a Scan Tool.
^ A history DTC will clear when 40 consecutive ignition cycles have occurred without a malfunction.
^ HVAC programmer battery voltage is interrupted.

TEST DESCRIPTION
3. Ensures that the DTC was not set in error.