
Connector Pin Function
| Pin No | Connector A (Blower) | Connector B (Main) |
| 1 | Low | Battery (+) |
| 2 | Common | ISG B+ |
| 3 | Ground | ILL+ (TAIL) |
| 4 | Middle Low | Sensor REF (+5V) |
| 5 | Middle High | Mode control actuator feedback |
| 6 | High | Temperature control actuator feedback |
| 7 | Intake actuator feedback | |
| 8 | Evaporator temperautre sensor (+) | |
| 9 | Ambient temperature sensor (+) | |
| 10 | Mode control actuator (Vent) | |
| 11 | Mode control actuator (DEF) | |
| 12 | Temperature control actuator (Cool) | |
| 13 | Temperature control actuator (Warm) | |
| 14 | Intake actuator (FRE) | |
| 15 | Intake actuator (REC) | |
| 16 | - | |
| 17 | - | |
| 18 | - | |
| 19 | Blower ON signal (Common) | |
| 20 | ILL - (RHEO) | |
| 21 | IGN2 | |
| 22 | IGN1 | |
| 23 | Blower INH | |
| 24 | Blower IS | |
| 25 | Blower PWM IN | |
| 26 | - | |
| 27 | Blower MAX signal | |
| 28 | IBU Active Low | |
| 29 | PTC realy 2 | |
| 30 | PTC ON signal | |
| 31 | - | |
| 32 | - | |
| 33 | CAN FD (High) | |
| 34 | CAN FD (Low) | |
| 35 | - | |
| 36 | Blower relay | |
| 37 | ECV (+) | |
| 38 | ECV (-) | |
| 39 | Sensor ground | |
| 40 | Ground |
1.Disconnect the negative (-) battery terminal.
2.Remove the front monitor.(Refer to Body Electrical System - "Front Monitor")
3.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.
Controller
Heater & A/C Control Unit (DATC)Hyundai Tucson (NX4) 2022-2025 Service Manual: ATF Warmer
- Description
• The ATF warmer is mounted on the valve body cover to reduce oil
viscosity friction by increasing oil temperature under cold condition,
which in turn improves fuel efficiency. It is serial mounted on the
entry of the Electronic Throttle Controller (ETC), as shown in the
...
Hyundai Tucson (NX4) 2022-2025 Service Manual: Fuel Pressure Test
- Fuel Pressure Test
1.Release the residual pressure in fuel line.(Refer to Fuel Delivery System - "Release Residual Pressure in Fuel Line")
• When removing the fuel pump relay, the Diagnostic Trouble Code
(DTC) will be occurred. Therefore delete the code with the diagnosti ...