B0337

CIRCUIT DESCRIPTION
The HVAC control module monitors the inside air temperature through an inside air temperature sensor. The inside air temperature sensor is a variable resistor. The HVAC control module supplies 5 volts to the inside air temperature sensor signal circuit, and provides a low reference circuit. When the air is cold, the sensor resistance and signal voltage are high. When the air is warm, the sensor resistance and signal voltage are low. The HVAC control module requests A/C compressor clutch engagement and controls the air temperature actuator door positions in order to maintain the selected air temperature on the HVAC control module.

CONDITIONS FOR RUNNING DTC
The ignition is turned ON.

CONDITIONS FOR SETTING THE DTC
The HVAC control module detects the signal circuit is less than 0.09 V.

ACTION TAKEN WHEN THE DTC SETS
The HVAC control module uses a default value.

CONDITIONS FOR CLEARING THE DTC
^ The DTC will become history if the HVAC control module no longer detects a failure.
^ The history DTC will clear after 50 fault free ignition cycles.
^ The DTC can be cleared with a scan tool.

DIAGNOSTIC AIDS
If condition not present refer to Testing for Intermittent and Poor Connections in Diagnostic Aids.

TEST DESCRIPTION

Steps 1-4:

Steps 5-12:

The numbers below refer to the step numbers on the diagnostic table.
2. The operating range of the sensor is between 0.09-4.90 volts. If the scan tool displays a value between 0-.08 volt or 4.91-5.0 volts, then the sensor is performing outside of its designed limits.
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.