B0184

CIRCUIT DESCRIPTION
The HVAC control module monitors the ambient light via a sunload sensor. The HVAC control module uses this information to calculate a solar correction that compensates for the effect of the sun on the vehicle inside air temperature. When the sensor is in direct sunlight, the signal voltage is low. When the sensor is shaded, the signal voltage is high.

CONDITIONS FOR RUNNING THE 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 (5 counts) or greater than 4.90 V (250 counts).

ACTION TAKEN WHEN THE DTC SETS
A default value will be used for the sensor data by the HVAC control module. The sensor reading displayed on the scan tool in the HVAC data list will be this 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 Diagrams.

TEST DESCRIPTION

Steps 1-6:

Steps 7-12:

The numbers below refer to the step numbers on the diagnostic table.
2. Scan tool uses a default value, this will not give accurate reading of sensor value if open or short to ground.
8. Tests for the possibility of a short to another 5 V reference circuit.