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B0338

DTC B0338 Inside Air Temperature Sensor Circuit Is Open:




DTC B0338 Inside Air Temperature Sensor Circuit Is Open:




CIRCUIT DESCRIPTION
The heater-A/C control receives an inside air temperature input from the inside air temperature sensor through Circuit 734. The inside air temperature sensor is grounded through circuit 61 to a sensor ground input in the heater-A/C control. This signal is used to display the inside air temperature on the heater-A/C control display and to determine the control of the vacuum solenoids. This value is stored in Keep Alive Memory (KAM) of the heater-A/C control.

CONDITIONS FOR SETTING THE DTC
^ The heater-A/C control will perform an internal check on the operation of the inside air temperature sensor.
^ The heater-A/C control detects a fault to inside air temperature sensor which may or may not be caused by an external fault.

ACTION TAKEN WHEN THE DTC SETS
Stores a DTC B0338 in the heater-A/C control memory.

CONDITIONS FOR CLEARING THE DTC
^ Under all fault conditions, the ignition must be cycled before this DTC can change from current to history.
^ A history DTC will clear after 100 drive cycles if the condition for the malfunction is no longer present.
^ Using a scan tool.

DIAGNOSTIC AIDS
^ The following conditions may cause a malfunction to a occur:
- A voltage spike in circuit 734.
- An open in circuit 734.
- A short to B+ in circuit 734.
- An open in circuit 61.

TEST DESCRIPTION
Numbers below refer to the step numbers on the diagnostic table.
1. Always perform the Heater-A/C Control Diagnostic System Check before attempting to diagnose a DTC B0338.
2. This test checks to see if the 5 volt pull-up voltage from the heater-A/C control through circuit 734 is seen at the inside air temperature sensor harness connector terminal A.
3. This test checks to see if the heater-A/C control is supplying a ground path through circuit 61 to the inside air temperature sensor harness connector terminal B.
7. Always clear DTCs after a repair procedure is complete.