B0159

Schematic:

CIRCUIT DESCRIPTION
The Instrument Panel Integration Module (IPM) monitors the outside air temperature via a temperature sensor. 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 IPM displays the outside air temperature on the heater A/C control head.

CONDITIONS FOR RUNNING THE DTC
The ignition is turned ON.

CONDITIONS FOR SETTING THE DTC
The IPM detects the signal circuit is less than 0.09 V (5 counts) or greater than 4.88 V (250 counts).

ACTION TAKEN WHEN THE DTC SETS
^ A default value of 2.5 V (128 counts) will be used for the sensor data by the IPM. The temperature displayed on the scan tool in the HVAC Sensors data list will be the default value. The actual sensor reading will be displayed on the scan tool in the Open/Short data list.
^ The heater A/C control head will display " - -" for outside air temperature.

CONDITIONS FOR CLEARING THE MIL/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 1-12:

The number(s) below refer to the step number(s) 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.