CLIMATE CONTROL UNIT INSPECTION [FULL-AUTO AIR CONDITIONER]

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1. Remove the climate control unit with the connector connected. (See CLIMATE CONTROL UNIT REMOVAL/INSTALLATION [FULL-AUTO AIR CONDITIONER].)

2. Switch the ignition to ON.

3. Connect the negative (-) lead of the tester to body ground.

4. By inserting the positive (+) lead of the tester into each climate control unit terminal, measure the voltage according to the terminal voltage table.

• If there is any malfunction, inspect the parts under “Inspection item (s)”.

― If the parts under “Inspection item (s)” are found to be normal (except for terminal 1M), replace the climate control unit.

― For terminal 1M, first try replacing the power MOS FET. If there is still any malfunction, replace the climate control unit.

Terminal Voltage Table (Reference)

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Terminal

Signal name

Connected to

Measurement condition

Voltage (V)

Inspection item (s)

1A^*7

—

—

—

—

—

1A^*8

R.H.D.

•  Driver-side air mix actuator

•  Passenger-side air mix actuator

•  Airflow mode actuator

Under any condition

1.0 or less

•  Related wiring harness

•  Climate control unit: terminal voltage (1C)

1B

—

—

—

—

—

1C

+5V

•  Driver-side air mix actuator

•  Passenger-side air mix actuator

•  Airflow mode actuator

•  Solar radiation sensor

•  Refrigerant pressure sensor^*4

Switch the ignition to ON

5

•  Related wiring harness

•  Driver-side air mix actuator

•  Passenger-side air mix actuator

•  Airflow mode actuator

•  Solar radiation sensor

•  Refrigerant pressure sensor^*4

•  Climate control unit: terminal voltage (1E)

Switch the ignition to Off

1.0 or less

1D

GND

Body ground

Under any condition

1.0 or less

•  Related wiring harness

1E

Sensor GND

•  Driver-side air mix actuator

•  Passenger-side air mix actuator

•  Airflow mode actuator

•  Evaporator temperature sensor

•  Refrigerant pressure sensor^*4

•  Heater core temperature sensor^*6

Under any condition

1.0 or less

•  Related wiring harness

•  Climate control unit: terminal voltage (1C)

1F

Solar radiation sensor (RH) input

Solar radiation sensor

Sunlight shined directly on the solar radiation sensor

4

•  Related wiring harness

•  Climate control unit: terminal voltage (1C)

•  Solar radiation sensor

Blocking light to solar radiation sensor

1.0 or less

1G

Potentiometer input

Driver-side air mix actuator

Set temperature at MAX HOT

4.3 or more

•  Related wiring harness

•  Driver-side air mix actuator

•  Climate control unit: terminal voltage (1C)

Set temperature at MAX COLD

1.0 or less

1H

Solar radiation sensor (LH) input

Solar radiation sensor

Sunlight shined directly on the solar radiation sensor

4

•  Related wiring harness

•  Climate control unit: terminal voltage (1C)

•  Solar radiation sensor

Blocking light to solar radiation sensor

1.0 or less

1I

Potentiometer input

Passenger-side air mix actuator

Set temperature at MAX COLD

1.0 or less

•  Related wiring harness

•  Passenger-side air mix actuator

•  Climate control unit: terminal voltage (1C)

Set temperature at MAX HOT

4.3 or more

1J

—

—

—

—

—

1K

Potentiometer input

Airflow mode actuator

VENT

4.3 or more

•  Related wiring harness

•  Airflow mode actuator

•  Climate control unit: terminal voltage (1C)

BI-LEVEL

3.4

HEAT

2.5

HEAT/DEF

1.6

DEFROSTER

0.7 or less

1L

Evaporator temperature sensor input

Evaporator temperature sensor

Compared with temperature detected by evaporator temperature sensor

Refer to graph 1

•  Related wiring harness

•  Evaporator temperature sensor

•  Climate control unit: terminal voltage (1E)

1M

Blower fan speed control

Power MOS FET

Fan stopped

1.0 or less

•  Related wiring harness

•  Power MOS FET

Fan: manual 1st

2.2

Fan: manual 7th

9.7

1N

Blower motor feedback

•  Blower motor

•  Power MOS FET

Fan stopped

B+

•  Power MOS FET

•  Blower motor

•  Blower relay

•  HEATER 40 A fuse

•  Power MOS FET replacement

•  Related wiring harness

Fan: manual 1st

9.8

Fan: manual 7th

0.4 or less

1O^*5

—

—

—

—

—

1O^*6

Heater core temperature sensor input

Heater core temperature sensor

Compared with temperature detected by heater core temperature sensor

Refer to graph 3

•  Related wiring harness

•  Heater core temperature sensor

•  Climate control unit: terminal voltage (1E)

1P

—

—

—

—

—

1Q

Motor operation (COLD)

Passenger-side air mix actuator

Moving towards HOT

1.0 or less

•  Related wiring harness

•  Passenger-side air mix actuator

Moving towards COLD

B+

1R

Motor operation (FRESH)

Air intake actuator

Moving towards RECIRCULATE

1.0 or less

•  Related wiring harness

•  Air intake actuator

Moving towards FRESH

B+

1S

Motor operation (HOT)

Passenger-side air mix actuator

Moving towards HOT

B+

•  Related wiring harness

•  Passenger-side air mix actuator

Moving towards COLD

1.0 or less

1T

Motor operation (RECIRCULATE)

Air intake actuator

Moving towards RECIRCULATE

B+

•  Related wiring harness

•  Air intake actuator

Moving towards FRESH

1.0 or less

1U

Motor operation (COLD)

Driver-side air mix actuator

Moving towards HOT

1.0 or less

•  Related wiring harness

•  Driver-side air mix actuator

Moving towards COLD

B+

1V

Motor operation (DEFROSTER)

Airflow mode actuator

Moving towards DEFROSTER

B+

•  Related wiring harness

•  Airflow mode actuator

Moving towards VENT

1.0 or less

1W

Motor operation (HOT)

Driver-side air mix actuator

Moving towards HOT

B+

•  Related wiring harness

•  Driver-side air mix actuator

Moving towards COLD

1.0 or less

1X

Motor operation (VENT)

Airflow mode actuator

Moving towards VENT

B+

•  Related wiring harness

•  Airflow mode actuator

Moving towards DEFROSTER

1.0 or less

2A

Illumination control

Instrument cluster

Headlight switch ON and panel light control switch at MAX

1.0 or less

•  Related wiring harness

•  Instrument cluster

Headlight switch ON and panel light control switch at MIN

11.5

2B

B+

ROOM 15 A fuse

Under any condition

B+

•  Related wiring harness

•  ROOM 15 A fuse

2C^*3

+5V

Refrigerant pressure sensor

Switch the ignition to ON

5

•  Related wiring harness

•  Refrigerant pressure sensor

•  Climate control unit: terminal voltage (2N)

Switch the ignition to Off

1.0 or less

2D

—

—

—

—

—

2E

MS_CAN_H

CAN related module

Because this terminal is for communication, good/no good judgment by terminal voltage is not possible.

•  Related wiring harness

2F

TNS signal

TNS relay

Headlight switch ON

B+

•  Related wiring harness

•  TNS relay

•  BCM

•  Headlight switch

Headlight switch OFF

1.0 or less

2G

MS_CAN_L

CAN related module

Because this terminal is for communication, good/no good judgment by terminal voltage is not possible.

•  Related wiring harness

2H

IG2

HEATER 10 A fuse

Switch the ignition to ON

B+

•  Related wiring harness

•  HEATER 10 A fuse

Switch the ignition to Off

1.0 or less

2I^*1

—

—

—

—

—

2I^*2

Heated windshield signal

Heated windshield relay

Engine ON and heated windshield switch OFF

B+

•  Related wiring harness

•  Heated windshield relay

Engine ON and approx. 5 s after heated windshield switch ON

1.0 or less

2J

Refrigerant pressure sensor input

Refrigerant pressure sensor

Compared with temperature detected by refrigerant pressure sensor

(See REFRIGERANT PRESSURE SENSOR INSPECTION [FULL-AUTO AIR CONDITIONER].)

•  Related wiring harness

•  Refrigerant pressure sensor

•  Climate control unit: terminal voltage (2C, 2N)^*3 (1C, 1E)^*4

2K

—

—

—

—

—

2L

—

—

—

—

—

2M

Cabin temperature sensor input

Cabin temperature sensor

Compared with temperature detected by cabin temperature sensor

Refer to graph 2

•  Related wiring harness

•  Cabin temperature sensor

•  Climate control unit: terminal voltage (2N)

2N

Cabin temperature sensor GND

•  Cabin temperature sensor

•  Refrigerant pressure sensor^*3

Under any condition

1.0 or less

•  Climate control unit: terminal voltage (2M, 2C)

2O

—

—

—

—

—

2P

—

—

—

—

—

Terminal	Signal name	Connected to	Measurement condition	Voltage (V)	Inspection item (s)
1A^*7	—	—	—	—	—
1A^*8	R.H.D.	• Driver-side air mix actuator • Passenger-side air mix actuator • Airflow mode actuator	Under any condition	1.0 or less	• Related wiring harness • Climate control unit: terminal voltage (1C)
1B	—	—	—	—	—
1C	+5V	• Driver-side air mix actuator • Passenger-side air mix actuator • Airflow mode actuator • Solar radiation sensor • Refrigerant pressure sensor^*4	Switch the ignition to ON	5	• Related wiring harness • Driver-side air mix actuator • Passenger-side air mix actuator • Airflow mode actuator • Solar radiation sensor • Refrigerant pressure sensor^*4 • Climate control unit: terminal voltage (1E)
Switch the ignition to Off	1.0 or less
1D	GND	Body ground	Under any condition	1.0 or less	• Related wiring harness
1E	Sensor GND	• Driver-side air mix actuator • Passenger-side air mix actuator • Airflow mode actuator • Evaporator temperature sensor • Refrigerant pressure sensor^4 • Heater core temperature sensor^6	Under any condition	1.0 or less	• Related wiring harness • Climate control unit: terminal voltage (1C)
1F	Solar radiation sensor (RH) input	Solar radiation sensor	Sunlight shined directly on the solar radiation sensor	4	• Related wiring harness • Climate control unit: terminal voltage (1C) • Solar radiation sensor
Blocking light to solar radiation sensor	1.0 or less
1G	Potentiometer input	Driver-side air mix actuator	Set temperature at MAX HOT	4.3 or more	• Related wiring harness • Driver-side air mix actuator • Climate control unit: terminal voltage (1C)
Set temperature at MAX COLD	1.0 or less
1H	Solar radiation sensor (LH) input	Solar radiation sensor	Sunlight shined directly on the solar radiation sensor	4	• Related wiring harness • Climate control unit: terminal voltage (1C) • Solar radiation sensor
Blocking light to solar radiation sensor	1.0 or less
1I	Potentiometer input	Passenger-side air mix actuator	Set temperature at MAX COLD	1.0 or less	• Related wiring harness • Passenger-side air mix actuator • Climate control unit: terminal voltage (1C)
Set temperature at MAX HOT	4.3 or more
1J	—	—	—	—	—
1K	Potentiometer input	Airflow mode actuator	VENT	4.3 or more	• Related wiring harness • Airflow mode actuator • Climate control unit: terminal voltage (1C)
BI-LEVEL	3.4
HEAT	2.5
HEAT/DEF	1.6
DEFROSTER	0.7 or less
1L	Evaporator temperature sensor input	Evaporator temperature sensor	Compared with temperature detected by evaporator temperature sensor	Refer to graph 1	• Related wiring harness • Evaporator temperature sensor • Climate control unit: terminal voltage (1E)
1M	Blower fan speed control	Power MOS FET	Fan stopped	1.0 or less	• Related wiring harness • Power MOS FET
Fan: manual 1st	2.2
Fan: manual 7th	9.7
1N	Blower motor feedback	• Blower motor • Power MOS FET	Fan stopped	B+	• Power MOS FET • Blower motor • Blower relay • HEATER 40 A fuse • Power MOS FET replacement • Related wiring harness
Fan: manual 1st	9.8
Fan: manual 7th	0.4 or less
1O^*5	—	—	—	—	—
1O^*6	Heater core temperature sensor input	Heater core temperature sensor	Compared with temperature detected by heater core temperature sensor	Refer to graph 3	• Related wiring harness • Heater core temperature sensor • Climate control unit: terminal voltage (1E)
1P	—	—	—	—	—
1Q	Motor operation (COLD)	Passenger-side air mix actuator	Moving towards HOT	1.0 or less	• Related wiring harness • Passenger-side air mix actuator
Moving towards COLD	B+
1R	Motor operation (FRESH)	Air intake actuator	Moving towards RECIRCULATE	1.0 or less	• Related wiring harness • Air intake actuator
Moving towards FRESH	B+
1S	Motor operation (HOT)	Passenger-side air mix actuator	Moving towards HOT	B+	• Related wiring harness • Passenger-side air mix actuator
Moving towards COLD	1.0 or less
1T	Motor operation (RECIRCULATE)	Air intake actuator	Moving towards RECIRCULATE	B+	• Related wiring harness • Air intake actuator
Moving towards FRESH	1.0 or less
1U	Motor operation (COLD)	Driver-side air mix actuator	Moving towards HOT	1.0 or less	• Related wiring harness • Driver-side air mix actuator
Moving towards COLD	B+
1V	Motor operation (DEFROSTER)	Airflow mode actuator	Moving towards DEFROSTER	B+	• Related wiring harness • Airflow mode actuator
Moving towards VENT	1.0 or less
1W	Motor operation (HOT)	Driver-side air mix actuator	Moving towards HOT	B+	• Related wiring harness • Driver-side air mix actuator
Moving towards COLD	1.0 or less
1X	Motor operation (VENT)	Airflow mode actuator	Moving towards VENT	B+	• Related wiring harness • Airflow mode actuator
Moving towards DEFROSTER	1.0 or less
2A	Illumination control	Instrument cluster	Headlight switch ON and panel light control switch at MAX	1.0 or less	• Related wiring harness • Instrument cluster
Headlight switch ON and panel light control switch at MIN	11.5
2B	B+	ROOM 15 A fuse	Under any condition	B+	• Related wiring harness • ROOM 15 A fuse
2C^*3	+5V	Refrigerant pressure sensor	Switch the ignition to ON	5	• Related wiring harness • Refrigerant pressure sensor • Climate control unit: terminal voltage (2N)
Switch the ignition to Off	1.0 or less
2D	—	—	—	—	—
2E	MS_CAN_H	CAN related module	Because this terminal is for communication, good/no good judgment by terminal voltage is not possible.	• Related wiring harness
2F	TNS signal	TNS relay	Headlight switch ON	B+	• Related wiring harness • TNS relay • BCM • Headlight switch
Headlight switch OFF	1.0 or less
2G	MS_CAN_L	CAN related module	Because this terminal is for communication, good/no good judgment by terminal voltage is not possible.	• Related wiring harness
2H	IG2	HEATER 10 A fuse	Switch the ignition to ON	B+	• Related wiring harness • HEATER 10 A fuse
Switch the ignition to Off	1.0 or less
2I^*1	—	—	—	—	—
2I^*2	Heated windshield signal	Heated windshield relay	Engine ON and heated windshield switch OFF	B+	• Related wiring harness • Heated windshield relay
Engine ON and approx. 5 s after heated windshield switch ON	1.0 or less
2J	Refrigerant pressure sensor input	Refrigerant pressure sensor	Compared with temperature detected by refrigerant pressure sensor	(See REFRIGERANT PRESSURE SENSOR INSPECTION [FULL-AUTO AIR CONDITIONER].)	• Related wiring harness • Refrigerant pressure sensor • Climate control unit: terminal voltage (2C, 2N)^3 (1C, 1E)^4
2K	—	—	—	—	—
2L	—	—	—	—	—
2M	Cabin temperature sensor input	Cabin temperature sensor	Compared with temperature detected by cabin temperature sensor	Refer to graph 2	• Related wiring harness • Cabin temperature sensor • Climate control unit: terminal voltage (2N)
2N	Cabin temperature sensor GND	• Cabin temperature sensor • Refrigerant pressure sensor^*3	Under any condition	1.0 or less	• Climate control unit: terminal voltage (2M, 2C)
2O	—	—	—	—	—
2P	—	—	—	—	—

*1 :Vehicles without heated windshield.

*2 :Vehicles with heated windshield.

*3 :L5, LF, MZR 2.0 DISI i-stop, L3 Turbo (European (L.H.D. U.K.) specs.)

*4 :L5, LF, L3 Turbo (Australian, General (L.H.D. R.H.D.) specs.)

*5 :Vehicles without i-stop.

*6 :Vehicles with i-stop.

*7 :L.H.D.

*8 :R.H.D.