Hyundai Elantra CN7: Seat Electrical

Seventh generation (CN7; 2021–2024) / Hyundai Elantra CN7 2021-2024 Workshop Manual / Body Electrical System / Seat Electrical

Power Seat Motor

Components and components location

Component Location

1. Lumber support motor
2. Reclining motor
3. Front height motor
4. Slide motor

5. Rear height motor
6. Reclining limit switch
7. Lumber support switch
8. Seat switch

Repair procedures

Inspection

Power Seat Motor

1.	Disconnect the connectors for each motor. [Slide Motor] [Rear Height Motor] [Front Height Motor] [Reclining Motor] [Lumbar Support Motor]

2.	With the battery connected directly to the motor terminals, check if the motors run smoothly.

3.	Reverse the connections and check that the motor turns in reverse.

4.	If there is an abnormality, replace the motors.

[Reclining Motor Limit Switch]

•	The power seat motor(IMS specification) mounted in this vehicle uses the hole sensor to calculate the maximum operation distance, so it does not require limit switch.

•	But, NON- IMS specification driver seat and passenger seat have limit switches in the motor in the back of the chairs.

1.	Disconnect the limit switch and operate the limit switch.

2.	Check for continuity between the terminals.

3.	Make sure that the seat operation is normal in the reverse after the maximum operation.

4.	If there is an abnormality, replace the limit switch.

Remove

Front Seat

1.	Disconnect the battery terminals.

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

Power Seat Control Switch

Repair procedures

Removal

1.	Disconnect the negative (-) battery terminal.

2.	Remove the front seat outer shield cover. (Refer to Body - "Front Seat Outer Shield Cover")

3.	Remove the power seat control switch (A) after loosening the screws.

Installation

1.	Install the power seat control switch after connecting the connector.

2.	Install the front seat outer shield cover.

3.	Connect the negative (-) battery terminal.

Seat Heater

Components and components location

Component Location

[Front Seat Heater]

1. Seat heater unit (Passenger only)
2. Seat cushion heater

3. Seat back heater

[Rear Seat Heater]

1. Seat heater unit

2. Seat cushion heater

Schematic diagrams

Circuit Diagram

[Front Seat Heater (Non-Air Ventilation)]

[Rear Seat Heater]

Repair procedures

Inspection

Front Seat Heater

Check for continuity and measure the resistance between terminals No 3 and No 6.

Standard value

Driver / Assists (cushion + back) : 1.65Ω±10%/23°C

Operate the seat heater after connecting the connector, and then check the thermostat by measuring the temperature of seat surface.

Standard value

1st : cushion : 36±2°C, back : 40±2°C

2st : cushion : 39±2°C, back : 45±2°C

3st : cushion : 42±2°C, back : 50±2°C

Rear Seat Heater

Check for continuity and measure the resistance between terminals No 1 and No 4.

Standard value

Rear seat : 1.67Ω±10%/20°C

Operate the seat heater after connecting the connector, and then check the thermostat by measuring the temperature of seat surface.

Standard value

High (Cushion) : 38±2°C

Low (Cushion) : 42±2°C

Seat Heater Unit Diagnosis Mode

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

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

•	Push IGN ON while pressing the seat heater button from IGN OFF.

•	Keep pressing IGN ON for more than three seconds before pressing it once againe for more than three seconds within 2 seconds.

•	All LED indicators on the driver and passenger seat button will blink 1 times.

After entering the diagnosis mode, you can check what failed by checking the blinking LED.

[Driver / Passenger Seat Heater]

Failure Indicator

Inspection Items

Detailed Inspections

Low : OFF
Mid : OFF
High : FLASHING

Low voltage detection

–	IGN1 voltage of 8.5 V or lower

Over voltage detection

–	IGN1 voltage of 16.5 V or lower

Low : FLASHING
Mid : FLASHING
High : FLASHING

Fuse (Short)

–	Disconnection or missing connector of heating seat B(+) line

Low : OFF
Mid : ON
High : FLASHING

NTC (Short / Disconnector)

–	NTC element failure

–	Short-circuit between NTC connector terminals

–	Disconnection in the NTC (+) wiring

–	Disconnection in the NTC (-) wiring

Low : FLASHING
Mid : FLASHING
High : FLASHING

Heater (Short / Disconnector)

–	Heating wire element failure

–	Short-circuit between heating wire connector terminals

–	Disconnection in the heating wire (+)

–	Disconnection in the heating wire (-)

Low : ON
Mid : ON
High : FLASHING

Loss of temperature feedback

–	Target temperature not reached within 40 minutes

[Rear Seat He7ater]

Failure Indicator

Inspection Items

Detailed Inspections

Low : OFF
High : OFF

Low voltage detection

–	IGN1 voltage of 8.5 V or lower

Over voltage detection

–	IGN1 voltage of 16.5 V or lower

Low : FLASHING
High : FLASHING

Fuse (Short)

–	Disconnection or missing connector of heating seat B(+) line

Low : OFF
High : FLASHING

NTC (Short / Disconnector)

–	NTC element failure

–	Short-circuit between NTC connector terminals

–	Disconnection in the NTC (+) wiring

–	Disconnection in the NTC (-) wiring

Low : FLASHING
High : FLASHING

Heater (Short / Disconnector)

–	Heating wire element failure

–	Short-circuit between heating wire connector terminals

–	Disconnection in the heating wire (+)

–	Disconnection in the heating wire (-)

Low : ON
High : FLASHING

Loss of temperature feedback

–	Target temperature not reached within 40 minutes

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

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

6.	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

Components

1. Driver seat heater switch 2. Passenger seat heater swtich	3. 2nd seat heater switch

Schematic diagrams

Circuit Diagram

Manual Seat Heater Switch

Connector Pin Information

[Connector A]

Pin No	Function	Pin No	Function
1	Low (Register specifications)	4	Middle Low (Register specifications)
2	Common (Register specifications)	5	Middle High (Register specifications)
3	Ground (Register specifications)	6	High (Register specifications)

[Connector B]

Pin No	Function	Pin No	Function
1	Battery (+)	21	IGN2
2	ISG B+	22	IGN1
3	ILL+ (TAIL)	23	Blower IS (PWM specifications)
4	Sensor REF (+5V)	24	-
5	Mode control actuator (Feedback)	25	-
6	Temperature control actuator (Feedback)	26	-
7	Intake actuator (Feedback)	27	Blower Max. On signal (Register specifications)
8	EVAP sensor (+)	28	-
9	AMB sensor (+)	29	PTC relay
10	Mode control actuator (Vent)	30	-
11	Mode control actuator (DEF)	31	-
12	Temperature control actuator (Cool)	32	-
13	Temperature control actuator (Warm)	33	P_CAN High
14	Intake actuator (FRE)	34	P_CAN Low
15	Intake actuator (REC)	35	Blower INH (PWM specifications)
16	HDT	36	Blower PWM (In) (PWM specifications)
17	-	37	ECV (+)
18	-	38	ECV (-)
19	Blower signal (On) (Register specifications)	39	Sensor ground
20	ILL- (RHEO)	40	Ground

DATC Seat Heater Switch

[Connector A]

Pin No	Function	Pin No	Function
1	Battery	9	IGN2
2	ILL+ (TAIL)	10	ISG Battery (+)
3	-	11	IGN1
4	LIN BUS	12	HTD
5	-	13	-
6	-	14	-
7	-	15	-
8	RHEO (ILL-)	16	Ground

[Rear Seat]

Repair procedures

Removal

[Manual Seat Heater Switch]

1.	Disconnect the negative (-) battery terminal.

2.	Remove heater & A/C control unt. (Refer to Heating, Ventilation and Air Conditioning - "Heater & A/C Control Unit (Manual")

[DATC Seat Heater Switch]

1.	Disconnect the negative (-) battery terminal.

2.	Remove heater & A/C control unt. (Refer to Heating, Ventilation and Air Conditioning - "Heater & A/C Control Unit (DATC")

[Rear Seat]

1.	Disconnect the negative (-) battery terminal.

2.	Remove the rear door window switch. (Refer to Power Windows - "Power Window Switch")

Installation

1.	Install the heater & A/C control unt.

2.	Connect the negative (-) battery terminal.

[Rear Seat Heater Switch]

1.	Install the rear door window switch.

2.	Connect the negative (-) battery terminal.

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.

Lumber Support Units

Repair procedures

Removal

1.	Disconnect the negative (-) battery terminal.

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

3.	Remove the seat back. (Refer to Body - "Front Seat Back Cover")

4.	Disconnect the lumber support motor connector (A).

5.	Separate the retaining clips (A) from the seat frame.

6.	Remove the lumber support assembly (A) after disengaging mounting clip.

Installation

1.	Install the lumbar support assembly.

2.	Install the seat back cover.

Install the front seat assembly.

•	Make sure that the connectors are plugged in properly.

•	Check the rear lumbar support system.

Inspection

Lumbar Support Motor

1.	Disconnect the connectors for each motor. [Lumbar Support Motor]

2.	With the battery connected directly to the motor terminals, check if the motors run smoothly.

3.	Reverse the connections and check that the motor turns in reverse.

4.	If there is an abnormality, replace the motors.

IMS(Integrated Memory System)

Description and operation DescriptionThe changed position of the seat by memorizing into the power seat unit with IMS switch controlling the optimal seat position set by the driver can be restored ...

Fuses And Relays

Components and components location Component Location[Engine Room]1. Engine room junction block[Interior Relay]1. ICU (Integrated Central Control Unit) Relay Box (Engine Compartment) Repair ...