Heater and A/C Control Unit (DATC) Repair Procedures

Self-Diagnosis

1. 1
   Self-Diagnosis Procedure.

   

   When performing self-diagnosis, the malfunction (self-diagnosis code) below will flash at 0.5-second intervals on the temperature display setting (driver side only), and the other symbols will be off.

2. 2
   Trouble Code Display

   1. Continuous Operation: DTC.

      

   2. Continuous Operation: DTC.

      

   3. STEP operation. A. Normal code or one trouble code is the same as continuous operation. B. Trouble code.

      

3. 3
   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
   0	Normal
   11	Incar sensor OPEN
   12	Incar sensor SHORT
   13	Ambient sensor OPEN
   14	Ambient air sensor SHORT
   17	Evaporator sensor OPEN
   18	Evaporator sensor SHORT
   19	Driver side temperature potentiometer OPEN or SHORT
   20	Driver side potentiometer malfunction
   21	Mode door potentiometer OPEN or SHORT
   22	Mode door potentiometer malfunction
   25	Intake door potentiometer OPEN or SHORT
   26	Intake door potentiometer malfunction
   32	Passenger side temperature potentiometer OPEN or SHORT
   33	Passenger side temperature sensor malfunction
   45	APT CAN signal error
   47	RPM CAN signal error
   48	Vehicle speed CAN signal error
   49	Engine coolant temperature CAN signal error
   71	Engine Control Solenoid Valve Malfunction

4. 4
   Fail-safe

   NO	Item	Fault	Fail-safe
   1	Incar sensor	Open or short	Monitor value 25 °C
   2	Ambient sensor	Open or short	Monitor value 20 °C
   3	Evaporator sensor	Open or short	Monitor value -2°C (28.4°F)
   4	Mode door potentiometer	Open or short	Fix the vent position when the Vent mode is selected. Fix the defrost position by selecting any mode except the Vent mode. Fix the vent position by selecting IG ON > OFF. Fix the defrost position when the floor purge is selected.
   5	Temperature door potentiometer (MTC)	Open or short	If the temperature setting is 1 ~ 7 steps, fix the position to maximum cooling. If the temperature setting is 8 ~ 15 steps, fix the position to maximum heating.
   6	Temperature door potentiometer (DATC)	Open or short	If the set temperature is 17 °C ~ 24 °C, fix the position to maximum cooling. If the set temperature is 25 °C ~ 32 °C, fix the position to maximum heating.
   7	Intake door potentiometer	Open or short	Fix the vent position when selecting the vent mode. Fix the defrost position by selecting any mode except the vent mode.
   8	Engine Speed	FFh or no reception	A/C OFF (Control with 0 rpm value)
   9	Vehicle Speed	FFh or no reception	A/C OFF (Control with value 0 km/h)
   10	Engine Coolant Temperature	FFh or no reception	Monitor value - 2 °C
   11	APS	FFh or no reception	Monitor value 5%
   12	R-TQACNAPVC (A/C compressor maximum torque limit)	FFh or no reception	A/C OFF (Control with value 0 N·m)
   13	R-PAKNK (APT sensor output value)	FFh or no reception	A/C OFF (Control with value 0 N·m)
   14	RLY-AC (A/C compressor relay activation)	FFh or no reception	A/C OFF

Replacement

1. 1
   Disconnect the negative (-) battery terminal.
2. 2
   Using a screwdriver or a trim remover, remove the center fascia panel (A).

   

3. 3
   Disconnect the A/C and heater controller connectors (A).

   

4. 4
   Remove the heater and A/C control assembly (A) from the center facia panel.

   

5. 5
   Install in the reverse order of removal.

   Make sure the connector is properly connected. Replace all damaged clips.