Hyundai Santa Cruz (NX4A OB) 2021-2025 Service Manual / Heating, Ventilation and Air Conditioning / Controller / Heater & A/C Control Unit (DATC)

Hyundai Santa Cruz: Controller / Heater & A/C Control Unit (DATC)

- Terminal Function

Connector Pin Function

Pin No	Connector A
1	Battery (+)
2	-
3	-
4	LIN BUS (Climate control)
5	-
6	-
7	-
8	-
9	IGN2
10	ISG B+
11	IGN1
12	-
13	Incar sensor (+)
14	-
15	Sensor Ground
16	Ground

- Self Diagnosis

1.Self-diagnosis process.

• When operating the self-diagnostics, the below fault(self-diagnostics code) will blink at 0.5 seconds interval on the temperature display settings(driver's side only) and the remaining symbols are OFF .

2.Fault code display

(1)Continuance operation : DTC code.

(2)Continuance operation : DTC code.

(3)STEP operation.A. Nomal or one fault code is same as a continuance operation. B. DTC code.

3.Self diagnostic code

Display	Fail description	Remarks
0	Normal
11	Interior Temperature Sensor Disconnection (OPEN)
12	Interior Temperature Sensor Short Circuit (SHORT)
13	Ambient Temperature Sensor Disconnection (OPEN)
14	Ambient Temperature Sensor Disconnection (SHORT)
17	Evaporator Temperature Sensor Disconnection (OPEN)
18	Evaporator Temperature Sensor Disconnection (SHORT)
19	Driver Seat Temperature Control Actuator Feedback Disconnection/Short Circuit (OPEN/SHORT)
19	SHORT Range [TEMP F/B Voltage ≤ 0.1V], OPEN Range [TEMP F/B Voltage ≥ 4.9V]
20	Dr TEMP DOOR POTENTIOMETER LOCKED	If the actuator cannot reach the desired control position in 20 seconds, then it is deemed to be locked.
21	MODE DOOR POTENTIOMETER Disconnection/Short Circuit (OPEN/SHORT)
	SHORT Range [DR MODE F/B Voltage ≤ 0.1V]
	OPEN Range [DR MODE F/B Voltage ≥ 4.9V]
22	MODE DOOR POTENTIOMETER LOCKED	If the actuator cannot reach the desired control position in 20 seconds, then it is deemed to be locked.
24	AUTO DEFOG SENSOR (SHORT)	ADS specification ONLY
25	INTAKE DOOR POTENTIOMETER Disconnection/Short Circuit (OPEN/SHORT)
	SHORT Range [INTAKE F/B Voltage ≤ 0.1V]
	OPEN Range [INTAKE F/B Voltage ≥ 4.9V]
26	INTAKE DOOR POTENTIOMETER LOCKED	If the actuator cannot reach the desired control position in 10 seconds, then it is deemed to be locked.
32	PASSENGER TEMP DOOR POTENTIOMETER Disconnection/Short Circuit (OPEN/SHORT)
	SHORT Range [TEMP F/B Voltage ≤ 0.1V]
	OPEN Range [TEMP F/B Voltage ≥ 4.9V]
33	PASSENGER TEMP DOOR POTENTIOMETER LOCKED	If the actuator cannot reach the desired control position in 20 seconds, then it is deemed to be locked.
43	DEFOG DOOR POTENTIOMETER Disconnection/Short Circuit (OPEN/SHORT)	ADS specification ONLY
	SHORT Range [DEFOG F/B Voltage ≤ 0.1V]
	OPEN Range [DEFOG F/B Voltage ≥ 4.9V]
44	DEF DOOR POTENTIOMETER LOCKED	If the actuator cannot reach the desired control position in 10 seconds, then it is deemed to be locked.
44	DEF DOOR POTENTIOMETER LOCKED	ADS specification ONLY
45	APT CAN Signal Error
47	RPM CAN SIGNAL Error
48	Vehicle Speed CAN Signal Error
49	Engine coolant temperature CAN Signal Error
71	ECV Fault (OPEN)
72	Communication error between the LCD module and control unit

4.FAIL SAFE

NO	SIGNAL / ITEM	Failure Criteria	Alternative Value in Case of Failure
1	INCAR SENSOR	Voltage ≤ 0.1V or Voltage ≥ 4.9V	Fixed at 22°C
2	AMB SENSOR	Voltage ≤ 0.1V or Voltage ≥ 4.9V	Fixed at 20°C
3	EVA SENSOR	Voltage ≤ 0.1V or Voltage ≥ 4.9V	Fixed at -2°C
4	TEMPERATURE CONTROL ACTUATOR	Voltage ≤ 0.1V or Voltage ≥ 4.9V	When the set temperature is 16.5°C → 22°C : Fixed to the maximum cooling.
4	TEMPERATURE CONTROL ACTUATOR	Voltage ≤ 0.1V or Voltage ≥ 4.9V	When the set temperature is 22.5°C → 27.5°C : Fixed to the maximum heating.
5	MODE CONTROL ACTUATOR	Voltage ≤ 0.1V or Voltage ≥ 4.9V	In case of vent mode : Vent position is fixed.
5	MODE CONTROL ACTUATOR	Voltage ≤ 0.1V or Voltage ≥ 4.9V	Other modes other than the vent : Defrost position is fixed.
6	INTAKE ACTUACOR	Voltage ≤ 0.1V or Voltage ≥ 4.9V	In case of outdoor ventilation mode : Outdoor ventilation position is fixed.
6	INTAKE ACTUACOR	Voltage ≤ 0.1V or Voltage ≥ 4.9V	In case of indoor ventilation mode : Indoor ventilation position is fixed.
7	AUTO DEFOGGING SENSOR (relative humidity)	OPEN / SHORT	Relative humidity : 0 %
8	Engine coolant temperature	OPEN / SHORT	90°C
9	ECV Feedback	OPEN	ECV output OFF

- Replacement

1.Disconnect the negative (-) battery terminal.

2.Remove the front monitor.(Refer to Body Electrical System - "Front Monitor")

3.Loosen the mounting screw, remove the heater & A/C control unit (A).

4.Install in the reverse order of removal.

• Replace any damaged clips.

• Make sure the connector is connected properly.

Heater & A/C Control Unit (Manual)

- Terminal Function Connector Pin Function Pin NoConnector APin NoConnector A 1Battery17IGN2 2ISG B+18IGN1 3ILL+ (TAIL)19Blower Relay 4Sensor REF (+5V)20Blower INH 5Mode Actuator Feedback2 ...

Heater Control Unit

- Components Location 1. Heater control unit - Terminal Function Connector Pin Function Pin NoConnector AConnector B 1Mode control actuator feedbackGround 2Intake actuator feedbackS ...

Other information:

Hyundai Santa Cruz (NX4A OB) 2021-2025 Service Manual: Rear Wheel Speed Sensor
- Components [2WD] 1. Rear wheel speed sensor [4WD] 1. Rear wheel speed sensor - Removal [2WD] 1.Loosen the wheel nuts slightly.Raise the vehicle, and make sure it is securely supported. 2.Remove the rear wheel and tire.(Refer to Suspension System - "Wheel") 3.Remove the rea ...

Hyundai Santa Cruz (NX4A OB) 2021-2025 Service Manual: Repair procedures
- Adjustment 1.Place the car on a flat surface and check whether the body and bed are well-aligned. 2.After loosening bed gate hinge (A) mounting bolt, adjust the bed by moving it up and down or from side to side. 3.After loosening the tail bed striker (B) mounting bolts, adjust the strik ...