Hyundai Elantra (CN7): Seat Electrical / Air Ventilation Seat

Hyundai Elantra (CN7) 2021-2025 Service Manual / Body Electrical System / Seat Electrical / Air Ventilation Seat

Components and components location

Component Location

[Front Ventilation Seat]

1. Ventilation seat blower

2.Ventilation seat unit

Schematic diagrams

Circuit Diagram

Connector Pin Information

Pin no	Connector A	Connector B	Connector C
1	Ventilation seat unit IGN 1	Ventilation heater power	blower ground
2	Driver blower power	Driver heater power	-
3	Driver blower spped	Passenger heater power	blower VSP
4	Driver RPM input	-	blower F/B
5	Illumination (+)	Driver heater ground	blower VCC
6	-	Driver ventilation heater ground
7	CAN Low	Driver ventilation power
8	CAN High	-
9	-	-
10	LIN	-
11	-	Passenger heater ground
12	Driver blower ground	Ventilation heater ground
13	Ventilation seat unit IGN 1
14	Passenger blower power
15	Passenger blower speed
16	Passenger blower RPM input
17	Illumination (-)
18	Detent
19	-
20	Driver NTC (+)
21	Passenger NTC (+)
22	Passenger NTC (-)
23	Driver NTC (-)
24	Passenger blower ground

Repair procedures

Removal

[Ventilation Blower]

1.	Disconnect the negative (-) battery terminal.

2.	Remove the front seat. (Refer to Body - "Front Seat Assembly")

3.	Remove the blower duct (A).

4.	Remove the blower FAN (A) after removing the screws.

[Ventilation Seat Unit]

1.	Disconnect the negative (-) battery terminal.

2.	Remove the front seat. (Refer to Body - "Front seat Assembly")

3.	Loosening the screws and then remove the ventilation seat unit (A) after disconnect the connectors.

Installation

[Ventilation Blower]

1.	Install the blower fan.

2.	Install the duct.

3.	Install the front seat assembly.

4.	Connect the negative (-) battery terminal.

[Ventilation Seat Unit]

1.	Install the ventilation seat unit.

2.	Install the front seat assembly.

3.	Connect the negative (-) battery terminal.

Inspection

Ventilating seat consists of three units : the ventilating seat unit for control, switch for input and and blower for output.

Diagnosis Mode

1.	You can enter the diagnosis mode by turning the heater seat button on.

2.	You can enter the diagnosis mode by referring to following description.

Press the heating wire switch as shown below.

1)	Press and hold the heating wire switch for 3 seconds or more.

2)	Release the switch for 3 seconds or less and press and hold it again for 1.5 - 3 seconds.

3)	Release the switch for 3 seconds or less and press and hold it again for 3 seconds or more.

When the vehicle enters the diagnostic mode, the three LEDs (Low, Mid, High) in the heating wire section blinks once for 0.5 seconds.

1)	When the vehicle enters the self-diagnostic mode, LEDs only work as those for heating wire seat switches.

2)	When two or more errors are detected, the LEDs sequentially blink at a 2-second interval for each error code.

After entering the diagnostic mode, check the LED status to identify the error.

Failure Indicator

LED (Flashing)

Inspection Items

Detailed Inspections

Low voltage detection

Low voltage that deviates from the operating voltage range was supplied.

Over voltage detection

Overvoltage that deviates from the operating voltage range was supplied.

Fuse (Short)

B+ fuse disconnection

IGN2 fuse disconnection

NTC/HEATER MAT (Short)

1)	NTC element failure

2)	Heater mat disconnection

3)	Heater+ wiring disconnection

4)	Heater system NTC disconnection (4.9 V or higher)

NTC/HEATER MAT (Disconnector)

1)	Short-circuit between the controller connector terminal and NTC

2)	Short-circuit between the controller connector terminal and heater

3)	Short-circuit in the heater system NTC wiring

4)	Short-circuit in the heater system heater+ wiring

Target temperature not reached

Target temperature not reached within 40 minutes

Short circuit of Ventilation blower power line

Short circuit of ventilation blower power line (short)

Power disconnection of ventilation blower

Disconnection or missing connector of ventilation power line

Short circuit of ventilation blower speed signal

Short circuit of ventilation blower speed signal (short)

Disconnection or missing connector of ventilation blower speed signal

Disconnection or missing connector of ventilation blower speed signal (VCC)

Disconnection or missing connector of ventilation blower speed signal

Disconnection or missing connector of ventilation blower speed signal (GND)

Short circuit of ventilation blower RPM signal (short)

Disconnection or missing connector of ventilation blower RPM signal

Disconnection or missing connector of ventilation blower RPM signal (GND)

Disconnection or missing connector of ventilation blower RPM signal

Disconnection or missing connector of ventilation blower RPM signal (GND)

6.	You can check the malfunctioning by checking the blinking LED.

7.	The failure data is recorded to the memory by the ventilation seat unit.

8.	Press the heating wire seat switch on the passenger side for 5 seconds or more to make the LED blink four times and delete the failure data in the memory.

9.	Pressing the IGN OFF button will end the diagnosis mode for the heater seat.

10.	You can check whether the heating seat system works properly after turning the IGN ON. If you want to check the error code, you can refer to the procedure of 2 above.

❮Seat Heater Switch

Components and components location Components1. Driver seat heater switch2. Passenger seat heater swtich3. 2nd seat heater switch Schematic diagrams Circuit DiagramManual Seat Heater SwitchConnector Pin Information[Connector A] Pin No Function Pin No Function 1Low (Register specifications)4Middle Low (Register specifications)2Common (Register specifications)5Middle High (Register specifications)3Ground (Register specifications)6High (Register specifications)[Connector B] Pin No Function Pin No Function 1Battery (+)21IGN22ISG B+22IGN13ILL+ (TAIL)23Blower IS (PWM specifications)4Sensor REF (+5V)24-5Mode control actuator (Feedback)25-6Temperature control actuator (Feedback)26-7Intake actuator (Feedback)27Blower Max.

Lumber Support Units❯

Repair procedures Removal1.Disconnect the negative (-) battery terminal.2.Remove the front seat assembly.(Refer to Body - "Front Seat Assembly")3.Remove the seat back.

Other information:

Hyundai Elantra (CN7) 2021-2025 Service Manual: Mode Control Actuator

Description and operation DescriptionThe mode control actuator is located at the heater unit.It adjusts the position of the mode door by operating the mode control actuator based on the signal of the A/C control unit. Pressing the mode select switch makes the mode control actuator shift in order of Vent → Bi-Level → Floor → Mix.