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On-Board Diagnostic System Description

On-Board Diagnostic System Description

HVAC control module detects malfunction, which may occur in the following areas.
- Inside temperature sensor
- A/C evaporator temperature sensor
- Sunload sensor (short circuit)
- Temperature control actuator
- Air flow control actuator
- Air intake control actuator
- Back-up power supply for HVAC control module
- Refrigerant pressure sensor signal data
- Engine speed signal data
- Vehicle speed signal data
- Engine coolant temperature signal data
- Outside air temperature sensor signal data
- CAN communication line

When HVAC control module detects malfunction, the "AUTO" display (1) flashes to warn and the diagnostic trouble code (DTC) is stored in the memory of the module. When diagnosing trouble, the DTC can be checked according to DTC Check.