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HVAC System (Diagnostics)

Diagnostics with Phenomenon

INSPECTION

1. Perform diagnosis according to the diagnosis procedure for the corresponding symptom listed in the symptom table.
2. If there are multiple symptoms, perform the diagnosis in the order of symptom number (1 --> 2 -->... --> 13).

SYMPTOM TABLE






DIAGNOSTIC PROCEDURE WITH PHENOMENON

1. NOTHING IS DISPLAYED ON THE SCREEN OR INDICATORS DO NOT ILLUMINATE.

TROUBLE SYMPTOM:
- When the AUTO button is pressed with IGN ON, nothing is displayed on the screen or indicators do not illuminate.
- Self diagnosis using A/C control panel does not operate.

Trouble causes:
- Control module power supply circuit failure
- A/C control panel power supply failure
- UART communication failure

WIRING DIAGRAM:

- Auto A/C






- Manual A/C
















2. AIR CONDITIONER DOES NOT STOP EVEN WHEN THE OFF SWITCH IS PRESSED. (VEHICLES WITH FULLY AUTOMATIC AIR CONDITIONER)

TROUBLE SYMPTOM:
Even when the OFF switch is pressed, the blower fan does not turn off, the inlet opening remains in FRESH mode, and the compressor does not turn off.

Trouble causes:
- UART communication failure
- A/C control panel failure
- Blower motor failure
- Intake door actuator failure
- Compressor failure









3. THE WINDSHIELD GLASS IS NOT CLEARED EVEN WHEN THE DEF SWITCH IS PRESSED. (VEHICLES WITH FULLY AUTOMATIC AIR CONDITIONER)

TROUBLE SYMPTOM:
Even when the DEF switch is pressed, the defroster indicator does not illuminate, the outlet opening is not set to DEF, the compressor does not turn on and the outlet opening is not set to FRESH.

Trouble causes:
- UART communication failure
- A/C control panel failure
- Mode door actuator failure
- Compressor failure
- Intake door actuator failure









4. COLD AIR NOT EMITTED

TROUBLE SYMPTOM:
Cold air not emitted.

Trouble causes:
- Airflow capacity failure
- Refrigerant pressure failure
- Air mix actuator (driver's) failure
- Air mix actuator (passenger's) failure (with left/right independent air conditioner only)
- Intake door actuator failure
- Evaporator sensor failure (vehicles with automatic air conditioner only)
- In-vehicle sensor failure (vehicles with automatic air conditioner only)
- Ambient sensor failure (vehicles with automatic air conditioner only)
- Sunload sensor failure (vehicles with automatic air conditioner only)












5. WARM AIR NOT EMITTED

TROUBLE SYMPTOM:
Warm air not emitted.

Trouble causes:
- Airflow capacity failure
- Coolant failure
- UART communication failure
- A/C control panel failure
- Air mix actuator (driver's) failure
- Air mix actuator (passenger's) failure (with left/right independent air conditioner only)
- Intake door actuator failure
- Evaporator sensor failure (vehicles with automatic air conditioner only)
- In-vehicle sensor failure (vehicles with automatic air conditioner only)
- Ambient sensor failure (vehicles with automatic air conditioner only)
- Sunload sensor failure (vehicles with automatic air conditioner only)












6. COMPARTMENT TEMPERATURE IS EXCESSIVELY LOWER THAN SETTING TEMPERATURE

TROUBLE SYMPTOM:
Compartment temperature is excessively lower than setting temperature.

Trouble causes:
- Large airflow capacity
- Refrigerant pressure failure
- UART communication failure
- A/C control panel failure
- Air mix actuator (driver's) failure
- Air mix actuator (passenger's) failure (with left/right independent air conditioner only)
- Evaporator sensor failure (vehicles with automatic air conditioner only)
- In-vehicle sensor failure (vehicles with automatic air conditioner only)
- Ambient sensor failure (vehicles with automatic air conditioner only)
- Sunload sensor failure (vehicles with automatic air conditioner only)









7. COMPARTMENT TEMPERATURE IS EXCESSIVELY HIGHER THAN SETTING TEMPERATURE

TROUBLE SYMPTOM:
Compartment temperature is excessively higher than setting temperature.

Trouble causes:
- Large airflow capacity
- UART communication failure
- A/C control panel failure
- Air mix actuator (driver s) failure
- Air mix actuator (passenger s) failure (with left/right independent air conditioner only)
- Intake door actuator failure
- Evaporator sensor failure (vehicles with automatic air conditioner only)
- In-vehicle sensor failure (vehicles with automatic air conditioner only)
- Ambient sensor failure (vehicles with automatic air conditioner only)
- Sunload sensor failure (vehicles with automatic air conditioner only)












8. AIR DOES NOT COME OUT, OR AIRFLOW CAPACITY IS INSUFFICIENT

TROUBLE SYMPTOM:
- Airflow capacity is insufficient.
- No air comes out even when the fan switch or fan dial is operated.
- There is a fan speed at which no air comes out.

Trouble causes:
- Airflow capacity failure
- UART communication failure
- A/C control panel failure
- Blower motor failure

Auto A/C

WIRING DIAGRAM:
















Manual A/C

WIRING DIAGRAM:












9. AIR GOES OUT OF CONTROL

TROUBLE SYMPTOM:
- The blower rotates even though the blower switch is not turned on.
- The blower motor continues to rotate at high speed. (Not adjustable.)


Trouble causes:
- Airflow capacity failure
- UART communication failure
- A/C control panel failure
- Blower motor failure

Auto A/C

WIRING DIAGRAM:













Manual A/C

WIRING DIAGRAM:











10. COLD AIR DOES NOT COME OUT EVEN WHEN THE A/C SWITCH IS PRESSED. THE GLASS CANNOT BE DEFOGGED. (COMPRESSOR DOES NOT OPERATE. (VARIABLE))

TROUBLE SYMPTOM:
Compressor does not operate even when the A/C switch is turned on and the fan switch is set to LO - HI.

Trouble causes:
Compressor failure

WIRING DIAGRAM:













11. UNABLE TO SWITCH SUCTION VENTS

TROUBLE SYMPTOM:
Even when the FRESH/RECIRC switch is pressed, the inlet opening does not switch to RECIRC --> FRESH or FRESH --> RECIRC.

Trouble causes:
Intake door actuator failure

WIRING DIAGRAM:













12. UNABLE TO SWITCH VENTS

TROUBLE SYMPTOM:
Unable to switch blow vents.

- Auto dual
Even when the mode switch is operated, outlet opening does not switch to FACE --> B/L --> FOOT --> F/D.
- Manual A/C
Selected mode does not work even when each mode switch is operated.

Trouble causes:
Mode door actuator failure






13. ILLUMINATION DOES NOT COME ON OR CANNOT DIM

TROUBLE SYMPTOM:
Even when the lighting switch is operated, the illumination does not come on. Even when the illumination control is operated, the illumination does not dim.

TROUBLE SYMPTOM:
Open circuit in illumination circuit

WIRING DIAGRAM:







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