B1318

CIRCUIT DESCRIPTION
The Instrument Panel Integration Module (IPM) monitors ambient light with the left sunload sensor. The left sunload sensor is an infrared light sensitive photodiode. The IPM uses this information to compensate for the effect of the sun on the inside air temperature of the vehicle. When the sensor is in direct sunlight, the signal voltage is low. When the sensor is shaded, the signal voltage is high. The IPM requests A/C compressor clutch engagement and controls the left air temperature door position in order to maintain the selected air temperature on the HVAC control module.

CONDITIONS FOR RUNNING THE DTC
The ignition is turned ON.

CONDITIONS FOR SETTING THE DTC
The IPM detects the driver solar sensor signal circuit is less than 0.09 volt (5 counts) or greater than 4.90 volts (250 counts).

ACTION TAKEN WHEN THE DTC SETS
A default value of 240 counts will be substituted for the sensor data by the IPM. The Driver Solar displayed on the scan tool in the HVAC Sensors data list will be the default value. The Left Solar Sensor displayed on the scan tool in the Open/Short Data list will be the actual value.

CONDITIONS FOR CLEARING THE DTC
^ The DTC will become history if the IPM 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.

TEST DESCRIPTION

Steps 1-4:

Steps 5-12:

The numbers below refer to the step numbers on the diagnostic table.
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.