Heater and A/C Control Unit (Automatic)

Components and Component Location

Components

Control Panel

Repair Procedures

Self-Diagnosis

1. 1
   Self-Diagnosis Procedure

   

2. 2
   How to Read Self-Diagnosis Codes: After the display panel flashes three times every 0.5 seconds, the corresponding trouble code flashes on the set temperature display every 0.5 seconds and shows two digits. Codes are displayed in numeric format.
3. 3
   Trouble Code Display

   1. Continuous Operation: One DTC.

      

   2. Continuous Operation: More than two DTCs.

      

   3. STEP Operation

      A.	Normal code or one trouble code is the same as continuous operation.

      B.	More than two DTCs.

      

4. 4
   If any diagnostic trouble codes are displayed during the inspection, check the causes of the malfunction by referring to the DTC troubleshooting.

   Display	Description of Malfunction
   00	Normal
   11	In-Car Sensor Open
   12	In-Car Sensor Short Circuit
   13	Ambient Sensor Open
   14	Ambient Air Sensor Short Circuit
   17	Evaporator Sensor Open
   18	Evaporator Sensor Short Circuit
   19	Air Temperature Door Potentiometer Open/Short - Actuator
   20	Air Temperature Door Potentiometer Malfunction - Actuator
   21	Mode Door Potentiometer Open/Short
   22	Mode Door Potentiometer Malfunction
   25	Intake Door Potentiometer Open
   26	Intake Door Potentiometer Short Circuit
   45	APT CAN signal error
   47	RPM CAN Signal Malfunction
   48	Vehicle Speed Signal Malfunction
   49	Engine Coolant Temperature CAN Signal Malfunction

5. 5
   Fail-safe

   NO.	Item	Fault	Fail-safe
   1	Vehicle Sensor	Open or short	Monitor value 25 °C
   2	Ambient Temperature Sensor	Open or short	Monitor value 20 °C
   3	Evaporator Temperature Sensor	Open or short	Monitor value -2°C (28.4°F)
   4	Engine coolant temperature sensor	Open or short	Monitor value -2°C (28.4°F)
   5	Temperature Control Actuator	Open or short	If the temperature setting is 17°C–24, 5 °C, fix the position at maximum cooling. If the temperature setting is 25°C–32°C, fix the position at maximum heating.
   6	Mode Control Actuator	Open or short	Fix the vent position when selecting the vent mode. Fix the defrost position by selecting any mode except the vent mode.
   7	Intake Control Actuator	Open or short	Fix the fresh air position when the fresh air mode is selected.
   			Fix the recirculation position when the recirculation mode is selected.
   9	ECV	Open	CF_Fatc_EcvFlt = 01H (malfunction) ECV OFF, A/C output OFF, torque 0 N·m
   10	VS (Vehicle Speed)	FFh or no reception	VS-TCU (from TCU2)
   11	VS TCU (vehicle speed calculated by TCU)	FFh or no reception	Monitor value 0 km/h
   12	N (Engine Speed)	NO request	Check with a value of 650 rpm
   13	F_N_ENG	FFh or no reception	Check with a value of 650 rpm
   14	TPS (Throttle Position Sensor Signal)	FFh or no reception	0%
   15	Temp _ ENG	FFh or no reception	Monitor value - 2 °C
   16	R _ TqAcnApvC (A/C Compressor Maximum Torque Limit)	FFh or no reception	0 N·m
   17	R _ PAcnC (APT sensor output value)	FFh or no reception	0 hPa (ECV OFF)
   18	RLI _ AC	NO request	Compressor OFF (ECV OFF)

Replacement

1. 1
   Disconnect the negative (-) battery terminal.
2. 2
   Remove the floor console assembly. (Refer to Body – Floor Console Assembly)
3. 3
   Remove the heater and A/C control unit (A).

   

4. 4
   Disconnect the connectors (A) from the heater and A/C control unit.

   

5. 5
   Install in the reverse order of removal.