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 ON (engine off or 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 2D), replace the climate control unit.

― For terminal 2D, first try replacing the blower fan controller. 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

B+

ROOM 15 A fuse

Under any condition

B+

•  Related wiring harness

•  ROOM 15 A fuse

1B

—

—

—

—

—

1C

IG1

C/U IG1 15 A fuse

Switch the ignition to ON

B+

•  Related wiring harness

•  C/U IG1 15 A fuse

Switch the ignition off

1.0 or less

1D

—

—

—

—

—

1E^*1

Seat warmer switch signal

Seat warmer control unit

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

•  Related wiring harness

1F

—

—

—

—

—

1G

—

—

—

—

—

1H

—

—

—

—

—

1I

—

—

—

—

—

1J

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 (1W)

1K

—

—

—

—

—

1L

+5V

•  Driver-side air mix actuator

•  Passenger-side air mix actuator

•  Airflow mode actuator

•  Solar radiation sensor

Under any condition

5

•  Related wiring harness

•  Driver-side air mix actuator

•  Passenger-side air mix actuator

•  Airflow mode actuator

•  Solar radiation sensor

•  Climate control unit: terminal voltage (1W)

1M

—

—

—

—

—

1N

Passenger compartment temperature sensor input

Passenger compartment temperature sensor

Compared with temperature detected by passenger compartment temperature sensor

Refer to graph 2

•  Related wiring harness

•  Passenger compartment temperature sensor

•  Climate control unit: terminal voltage (1W)

1O

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

1P

Potentiometer input

Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator

Set temperature at MAX HOT

4.3 or more

•  Related wiring harness

•  Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator

•  Climate control unit: terminal voltage (1W)

Set temperature at MAX COLD

1.0 or less

1Q

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

1R

Potentiometer input

Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator

Set temperature at MAX HOT

4.3 or more

•  Related wiring harness

•  Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator

•  Climate control unit: terminal voltage (1W)

Set temperature at MAX COLD

1.0 or less

1S

—

—

—

—

—

1T

Potentiometer input

Airflow mode actuator

VENT

4.3 or more

•  Related wiring harness

•  Airflow mode actuator

•  Climate control unit: terminal voltage (1W)

BI-LEVEL

3.4

HEAT

2.5

HEAT/DEF

1.6

DEFROSTER

0.72 or less

1U

GND

Body ground

Under any condition

1.0 or less

•  Related wiring harness

1V

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 (1L)

•  Solar radiation sensor

Blocking light to solar radiation sensor

1.0 or less

1W

Sensor GND

•  Driver-side air mix actuator

•  Passenger-side air mix actuator

•  Passenger compartment temperature sensor

•  Airflow mode actuator

•  Evaporator temperature sensor

Under any condition

1.0 or less

•  Related wiring harness

•  Climate control unit: terminal voltage (1L)

1X

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 (1L)

•  Solar radiation sensor

Blocking light to solar radiation sensor

1.0 or less

2A

—

—

—

—

—

2B

—

—

—

—

—

2C

IG2

Front body control module (FBCM)

Switch the ignition ON (engine off or on)

B+

•  Related wiring harness

•  Front body control module (FBCM)

Switch the ignition off

3.36 or less

2D

Blower fan speed control

Blower fan controller

(See Blower Fan Speed Control Signal)

•  Related wiring harness

•  Blower fan controller

2E

Motor operation (HOT)

Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator

Moving towards HOT

B+

•  Related wiring harness

•  Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator

Moving towards COLD

1.0 or less

2F

Motor operation (HOT)

Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator

Moving towards HOT

B+

•  Related wiring harness

•  Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator

Moving towards COLD

1.0 or less

2G

Motor operation (COLD)

Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator

Moving towards HOT

1.0 or less

•  Related wiring harness

•  Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator

Moving towards COLD

B+

2H

Motor operation (COLD)

Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator

Moving towards HOT

1.0 or less

•  Related wiring harness

•  Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator

Moving towards COLD

B+

2I

Motor operation (VENT)

Airflow mode actuator

Moving towards VENT

B+

•  Related wiring harness

•  Airflow mode actuator

Moving towards DEFROSTER

1.0 or less

2J

Motor operation (FRESH)

Air intake actuator

Moving towards RECIRCULATE

1.0 or less

•  Related wiring harness

•  Air intake actuator

Moving towards FRESH

B+

2K

Motor operation (DEFROSTER)

Airflow mode actuator

Moving towards DEFROSTER

B+

•  Related wiring harness

•  Airflow mode actuator

Moving towards VENT

1.0 or less

2L

Motor operation (RECIRCULATE)

Air intake actuator

Moving towards RECIRCULATE

B+

•  Related wiring harness

•  Air intake actuator

Moving towards FRESH

1.0 or less

Terminal	Signal name	Connected to	Measurement condition	Voltage (V)	Inspection item (s)
1A	B+	ROOM 15 A fuse	Under any condition	B+	• Related wiring harness • ROOM 15 A fuse
1B	—	—	—	—	—
1C	IG1	C/U IG1 15 A fuse	Switch the ignition to ON	B+	• Related wiring harness • C/U IG1 15 A fuse
Switch the ignition off	1.0 or less
1D	—	—	—	—	—
1E^*1	Seat warmer switch signal	Seat warmer control unit	Because this terminal is for communication, good/no good judgment by terminal voltage is not possible.	• Related wiring harness
1F	—	—	—	—	—
1G	—	—	—	—	—
1H	—	—	—	—	—
1I	—	—	—	—	—
1J	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 (1W)
1K	—	—	—	—	—
1L	+5V	• Driver-side air mix actuator • Passenger-side air mix actuator • Airflow mode actuator • Solar radiation sensor	Under any condition	5	• Related wiring harness • Driver-side air mix actuator • Passenger-side air mix actuator • Airflow mode actuator • Solar radiation sensor • Climate control unit: terminal voltage (1W)
1M	—	—	—	—	—
1N	Passenger compartment temperature sensor input	Passenger compartment temperature sensor	Compared with temperature detected by passenger compartment temperature sensor	Refer to graph 2	• Related wiring harness • Passenger compartment temperature sensor • Climate control unit: terminal voltage (1W)
1O	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
1P	Potentiometer input	Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator	Set temperature at MAX HOT	4.3 or more	• Related wiring harness • Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator • Climate control unit: terminal voltage (1W)
Set temperature at MAX COLD	1.0 or less
1Q	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
1R	Potentiometer input	Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator	Set temperature at MAX HOT	4.3 or more	• Related wiring harness • Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator • Climate control unit: terminal voltage (1W)
Set temperature at MAX COLD	1.0 or less
1S	—	—	—	—	—
1T	Potentiometer input	Airflow mode actuator	VENT	4.3 or more	• Related wiring harness • Airflow mode actuator • Climate control unit: terminal voltage (1W)
BI-LEVEL	3.4
HEAT	2.5
HEAT/DEF	1.6
DEFROSTER	0.72 or less
1U	GND	Body ground	Under any condition	1.0 or less	• Related wiring harness
1V	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 (1L) • Solar radiation sensor
Blocking light to solar radiation sensor	1.0 or less
1W	Sensor GND	• Driver-side air mix actuator • Passenger-side air mix actuator • Passenger compartment temperature sensor • Airflow mode actuator • Evaporator temperature sensor	Under any condition	1.0 or less	• Related wiring harness • Climate control unit: terminal voltage (1L)
1X	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 (1L) • Solar radiation sensor
Blocking light to solar radiation sensor	1.0 or less
2A	—	—	—	—	—
2B	—	—	—	—	—
2C	IG2	Front body control module (FBCM)	Switch the ignition ON (engine off or on)	B+	• Related wiring harness • Front body control module (FBCM)
Switch the ignition off	3.36 or less
2D	Blower fan speed control	Blower fan controller	(See Blower Fan Speed Control Signal)	• Related wiring harness • Blower fan controller
2E	Motor operation (HOT)	Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator	Moving towards HOT	B+	• Related wiring harness • Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator
Moving towards COLD	1.0 or less
2F	Motor operation (HOT)	Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator	Moving towards HOT	B+	• Related wiring harness • Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator
Moving towards COLD	1.0 or less
2G	Motor operation (COLD)	Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator	Moving towards HOT	1.0 or less	• Related wiring harness • Driver-side (L.H.D.) / passenger-side (R.H.D.) air mix actuator
Moving towards COLD	B+
2H	Motor operation (COLD)	Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator	Moving towards HOT	1.0 or less	• Related wiring harness • Passenger-side (L.H.D.) / driver-side (R.H.D.) air mix actuator
Moving towards COLD	B+
2I	Motor operation (VENT)	Airflow mode actuator	Moving towards VENT	B+	• Related wiring harness • Airflow mode actuator
Moving towards DEFROSTER	1.0 or less
2J	Motor operation (FRESH)	Air intake actuator	Moving towards RECIRCULATE	1.0 or less	• Related wiring harness • Air intake actuator
Moving towards FRESH	B+
2K	Motor operation (DEFROSTER)	Airflow mode actuator	Moving towards DEFROSTER	B+	• Related wiring harness • Airflow mode actuator
Moving towards VENT	1.0 or less
2L	Motor operation (RECIRCULATE)	Air intake actuator	Moving towards RECIRCULATE	B+	• Related wiring harness • Air intake actuator
Moving towards FRESH	1.0 or less

*1 :With seat warmer

Blower Fan Speed Control Signal

Fan stopped

ac5jjw00007748

Climate control unit terminal

• 2D(+)—body ground(-)

Oscilloscope setting

• 5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

• Switch the ignition ON (engine off or on)

Manual 1st

ac5jjw00007749

Climate control unit terminal

• 2D(+)—body ground(-)

Oscilloscope setting

• 5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

• Switch the ignition ON (engine off or on)

• Airflow mode: VENT

• Air intake mode: RECIRCULATE

Manual 3rd

ac5jjw00007750

Climate control unit terminal

• 2D(+)—body ground(-)

Oscilloscope setting

• 5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

• Switch the ignition ON (engine off or on)

• Airflow mode: VENT

• Air intake mode: RECIRCULATE

Manual 7th

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Climate control unit terminal

• 2D(+)—body ground(-)

Oscilloscope setting

• 5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

• Switch the ignition ON (engine off or on)

• Airflow mode: VENT

• Air intake mode: RECIRCULATE