B0272

CIRCUIT DESCRIPTION
The recirculation actuator is an electronic stepper motor with a feedback potentiometer. The Instrument Panel Integrated Module (IPM) determines the position of the recirculation door based on the voltage from the potentiometer. When the airflow is being recirculated, the voltage is low. When outside air is being admitted, voltage is high. The IPM controls the recirculation door in either the recirculation or the outside air position as selected by the vehicle occupants.

CONDITIONS FOR RUNNING THE DTC
The ignition is turned ON.

CONDITIONS FOR SETTING THE DTC
The IPM detects the signal is less than 5 counts (0.1 V) or greater than 250 counts (4.9 V).

ACTION TAKEN WHEN THE DTC SETS
^ The recirculation door will be set to the outside air position.
^ If B0272 sets during a calibration/recalibration event the IPM will no longer issue commands to the actuator and will not perform a calibration/recalibration until the door position feedback fault is corrected.

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.

DIAGNOSTIC AIDS
^ A disconnected or broken door/linkage may also set this DTC during calibration/recalibration by allowing the actuator to travel to its minimum internal stop (over travel condition).
^ If the condition is not present, refer to Testing for Intermittent and Poor Connections in Diagrams.

TEST DESCRIPTION

Steps 1-4:

Steps 5-16:

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.
5. Tests for a short to ground in the 5-volt reference circuit.