TSB-23-55-003

SUBJECT:
CORRECTION/ADDITION OF INSPECTION PROCEDURE
AND TROUBLE SYMPTOM CHART FOR AIR
CONDITIONER – SERVICE MANUAL REVISION
NO.:
TSB-23-55-003
DATE:
March 2023
MODEL:
2018-21 Outlander PHEV
CIRCULATE TO:
[ ] GENERAL MANAGER
[ X ] PARTS MANAGER
[ X ] TECHNICIAN
[ X ] SERVICE ADVISOR
[ X ] SERVICE MANAGER
[ X ] WARRANTY PROCESSOR
[ ] SALES MANAGER
PURPOSE
This TSB provides corrections and additional information for the Heater, Air Conditioning
and Ventilation section of the Service Manual.
AFFECTED VEHICLES
• 2018-2021 Outlander PHEV
AFFECTED SERVICE MANUAL
• 2018-2021 Outlander PHEV Service
Manual
PROCEDURE
Please use the attached chart as a guide to replace or add the indicated pages of the
affected Service Manual, Group 55 Heater, Air Conditioning and Ventilation.
Copyright 2023, Mitsubishi Motors North America, Inc.
The information contained in this bulletin is subject to change. For the latest version of this document, go to the
Mitsubishi Dealer Link, MEDIC, or the Mitsubishi Service Information website (www.mitsubishitechinfo.com).
3/24/2023
1 of 16
(5280/MSB22M55001A)
ATTACHED CHART
OUTLANDER PHEV
Applicable manual
2018
OUTLANDER PHEV
Service Manual
2019
OUTLANDER PHEV
Service Manual
2020
OUTLANDER PHEV
Service Manual
2021
OUTLANDER PHEV
Service Manual
3/24/2023
Pub. No.
MSCD-027B-2018
MSCD-027B-2019
MSCD-027B-2020
MSCD-027B-2021
Applicable title
HEATER, AIR CONDITIONING AND VENTILATION
└ TROUBLESHOOTING
└ TROUBLE SYMPTOM CHART
HEATER, AIR CONDITIONING AND VENTILATION
└ TROUBLESHOOTING
└ SYMPTOM PROCEDURES
└ INSPECTION PROCEDURE 11: Heater controller assembly (A/CECU) power supply system
HEATER, AIR CONDITIONING AND VENTILATION
└TROUBLESHOOTING
└ SYMPTOM PROCEDURES
└ Added below “INSPECTION PROCEDURE 14: The A/C
compressor does not stop. (cut in unintentionally)”
HEATER, AIR CONDITIONING AND VENTILATION
└ TROUBLESHOOTING
└ TROUBLE SYMPTOM CHART
HEATER, AIR CONDITIONING AND VENTILATION
└ TROUBLESHOOTING
└ SYMPTOM PROCEDURES
└ INSPECTION PROCEDURE 11: Heater controller assembly (A/CECU) power supply system
HEATER, AIR CONDITIONING AND VENTILATION
└TROUBLESHOOTING
└ SYMPTOM PROCEDURES
└ Added below “INSPECTION PROCEDURE 14: The A/C
compressor does not stop. (cut in unintentionally)”
HEATER, AIR CONDITIONING AND VENTILATION
└ TROUBLESHOOTING
└ TROUBLE SYMPTOM CHART
HEATER, AIR CONDITIONING AND VENTILATION
└ TROUBLESHOOTING
└ SYMPTOM PROCEDURES
└ INSPECTION PROCEDURE 11: Heater controller assembly (A/CECU) power supply system
HEATER, AIR CONDITIONING AND VENTILATION
└TROUBLESHOOTING
└ SYMPTOM PROCEDURES
└ Added below “INSPECTION PROCEDURE 14: The A/C
compressor does not stop. (cut in unintentionally)”
HEATER, AIR CONDITIONING AND VENTILATION
└ TROUBLESHOOTING
└ TROUBLE SYMPTOM CHART
HEATER, AIR CONDITIONING AND VENTILATION
└ TROUBLESHOOTING
└ SYMPTOM PROCEDURES
└ INSPECTION PROCEDURE 11: Heater controller assembly (A/CECU) power supply system
HEATER, AIR CONDITIONING AND VENTILATION
└TROUBLESHOOTING
└ SYMPTOM PROCEDURES
└ Added below “INSPECTION PROCEDURE 14: The A/C
compressor does not stop. (cut in unintentionally)”
2 of 16
Contents
Attached
sheet 28
Attached
sheet 29
Attached
sheet 36, 37
Attached
sheet 30
Attached
sheet 31
Attached
sheet 36, 37
Attached
sheet 32
Attached
sheet 33
Attached
sheet 36, 37
Attached
sheet 34
Attached
sheet 35
Attached
sheet 36, 37
(5280/MSB22M55001A)
Attached sheet 28
55-93
HEATER, AIR CONDITIONING AND VENTILATION
TROUBLESHOOTING
Trouble symptom
Inspection
procedure No.
Reference page
The blower air volume cannot be changed
4
P.55-97
The inside/outside air changeover is impossible
5
P.55-99
A/C outlet air temperature cannot be set
6
P.55-101
Air outlets changeover is impossible
7
P.55-102
Ambient temperature sensor system
8
P.55-104
A/C pressure sensor system
9
P.55-105
Blower motor power supply system
10
P.55-105
Heater controller assembly (A/C-ECU) power supply system
11
P.55-106
Heater does not work at all, heater does not work quickly.
12
P.55-108
Cannot communicate with the A/C compressor.
13
P.55-111
The A/C compressor does not stop (runs unintentionally)
14
P.55-113
SYMPTOM PROCEDURES
INSPECTION PROCEDURE 1: Communication with the M.U.T.-IIISE is not possible.
TROUBLESHOOTING HINTS
.
TECHNICAL DESCRIPTION (COMMENT)
x Malfunction of the heater controller assembly
(A/C-ECU)
x Check and repair the power supply circuit
system.
If communication with all other systems is not
possible, there is a high possibility that there is a
malfunction of the diagnosis line. If only the A/C
system cannot communicate with the M.U.T.-IIISE,
the heater controller assembly (A/C-ECU) may be
defective.
.
DIAGNOSIS
1. Using scan tool (M.U.T.-IIISE), diagnose CAN bus
line.
.
Inspection Procedure 2: Cool air does not come.
TROUBLESHOOTING HINTS
.
TECHNICAL DESCRIPTION (COMMENT)
If the blower air temperature cannot be cool when
turning A/C switch ON and lowering the preset
temperature, inadequate refrigerant quantity,
sensors, malfunction of A/C compressor, malfunction
of A/C pipe solenoid valve, harness or connectors
may be suspected.
.
x The wiring harness or connectors may have
loose, corroded, or damaged terminals, or
terminals pushed back in the connector
x Malfunction of A/C compressor
x The refrigerant quantity is inadequate.
x Malfunction of the A/C pipe solenoid valve
x Insufficiently charged main drive lithium-ion
battery

Electric heater (electric heater-ECU) power supply system
15
Attached sheet 36
When the air conditioning is operating, the air volume becomes lower
than the set air volume and the air volume cannot be changed.
16
Attached sheet 37
3/24/2023
3 of 16
(5280/MSB22M55001A)
Attached sheet 29
HEATER, AIR CONDITIONING AND VENTILATION
TROUBLESHOOTING
55-107
DIAGNOSIS
Required Special Tools:
x MB991223: Harness Set
x MB992006: Extra Fine Probe
STEP 1. Using scan tool (M.U.T.-IIISE), check whether the
other system DTC is set.
Check that the ETACS-ECU has not set a DTC.
CAUTION
To prevent damage to scan tool (M.U.T.-IIISE), always turn
the electric motor switch to the "LOCK" (OFF) position
before connecting or disconnecting scan tool
(M.U.T.-IIISE).
(1) Connect scan tool (M.U.T.-IIISE). Refer to "How to connect
the Scan Tool (M.U.T.-IIISE) P.54A-6".
(2) Turn the electric motor switch from "LOCK" (OFF) position
to "ON" position.
(3) Check if DTC is set.
(4) Turn the electric motor switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Carry out the diagnostic trouble code procedures
(Refer to GROUP 54A  ETACS-ECU,
diagnostic trouble code chart P.54A-433).
NO : Go to Step 2.
STEP 2. Measure the voltage at the heater controller
assembly (A/C-ECU) connector.
(1) Disconnect the connector, and measure at the wiring
harness side.
(2) Power supply mode of the electric motor switch: OFF o ON
(3) Voltage between IG1 terminal and body ground
OK: The voltage should measure approximately 12
volts (battery positive voltage).
Q: Is the check result normal?
YES : Go to Step 4.
NO : Go to Step 3.

IGCT control relay
STEP 3. Check of open circuit in IG1 line between
ETACS-ECU connector and heater controller assembly
 (A/C-ECU) connector.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to GROUP 00  How
to Use Troubleshooting/Inspection Service Points 
How to Cope with Intermittent Malfunction P.00-17).
NO : Repair the connector(s) or wiring harness.
3/24/2023
4 of 16
(5280/MSB22M55001A)
Attached sheet 30 (1/2)
55-98
HEATER, AIR CONDITIONING AND VENTILATION
TROUBLESHOOTING
TROUBLE SYMPTOM CHART
M1554005003309
Trouble symptom
Inspection procedure No.
Reference page
Communication with the scan tool (M.U.T.-IIISE) is not possi- 1
ble
P.55-98
Cool air does not come
2
P.55-98
The blower does not work
3
P.55-100
The blower air volume cannot be changed
4
P.55-103
The inside/outside air changeover is impossible
5
P.55-104
A/C outlet air temperature cannot be set
6
P.55-106
Air outlets changeover is impossible
7
P.55-108
Ambient temperature sensor system
8
P.55-110
A/C pressure sensor system
9
P.55-111
Blower motor power supply system
10
P.55-111
Heater controller assembly (A/C-ECU) power supply system
11
P.55-112
Heater does not work at all, heater does not work quickly.
12
P.55-115
Cannot communicate with the A/C compressor.
13
P.55-118
The A/C compressor does not stop (runs unintentionally)
14
P.55-119

Attached sheet 30 (2/2)
SYMPTOM PROCEDURES
INSPECTION PROCEDURE 1: Communication with the M.U.T.-IIISE is not possible.
TROUBLESHOOTING HINTS
.
TECHNICAL DESCRIPTION (COMMENT)
If communication with all other systems is not possible, there is a high possibility that there is a malfunction of the diagnosis line. If only the A/C system
cannot communicate with the M.U.T.-IIISE, the
heater controller assembly (A/C-ECU) may be defective.
.
x Malfunction of the heater controller assembly
(A/C-ECU)
x Check and repair the power supply circuit system.
.
DIAGNOSIS
1. Using scan tool (M.U.T.-IIISE), diagnose CAN bus
line.
Inspection Procedure 2: Cool air does not come.
TROUBLESHOOTING HINTS
.
TECHNICAL DESCRIPTION (COMMENT)
If the blower air temperature cannot be cool when
turning A/C switch ON and lowering the preset temperature, inadequate refrigerant quantity, sensors,
malfunction of A/C compressor, malfunction of A/C
pipe solenoid valve, harness or connectors may be
suspected.
.
3/24/2023
x The wiring harness or connectors may have
loose, corroded, or damaged terminals, or terminals pushed back in the connector
x Malfunction of A/C compressor
x The refrigerant quantity is inadequate.
x Malfunction of the A/C pipe solenoid valve
x Insufficiently charged main drive lithium-ion battery
5 of 16
(5280/MSB22M55001A)
Attached sheet 30 (2/2)
Electric heater (electric heater-ECU) power supply system
15
Attached sheet 36
When the air conditioning is operating, the air volume becomes lower
than the set air volume and the air volume cannot be changed.
16
Attached sheet 37
3/24/2023
6 of 16
(5280/MSB22M55001A)
Attached sheet 31
HEATER, AIR CONDITIONING AND VENTILATION
TROUBLESHOOTING
55-113
DIAGNOSIS
Required Special Tools:
x MB991223: Harness Set
x MB992006: Extra Fine Probe
STEP 1. Using scan tool (M.U.T.-IIISE), check whether the
other system DTC is set.
Check that the ETACS-ECU has not set a DTC.
CAUTION
To prevent damage to scan tool (M.U.T.-IIISE), always turn
the electric motor switch to the "LOCK" (OFF) position
before connecting or disconnecting scan tool
(M.U.T.-IIISE).
(1) Connect scan tool (M.U.T.-IIISE). Refer to "How to connect
the Scan Tool (M.U.T.-IIISE) P.54A-6".
(2) Turn the electric motor switch from "LOCK" (OFF) position
to "ON" position.
(3) Check if DTC is set.
(4) Turn the electric motor switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Carry out the diagnostic trouble code procedures
(Refer to GROUP 54A  ETACS-ECU, diagnostic
trouble code chart P.54A-446).
NO : Go to Step 2.
STEP 2. Measure the voltage at the heater controller
assembly (A/C-ECU) connector.
(1) Disconnect the connector, and measure at the wiring
harness side.
(2) Power supply mode of the electric motor switch: OFF o ON
(3) Voltage between IG1 terminal and body ground
OK: The voltage should measure approximately 12
volts (battery positive voltage).
Q: Is the check result normal?
YES : Go to Step 4.
NO : Go to Step 3.

IGCT control relay
STEP 3. Check of open circuit in IG1 line between
ETACS-ECU connector and heater controller assembly
 (A/C-ECU) connector.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to GROUP 00  How
to Use Troubleshooting/Inspection Service Points 
How to Cope with Intermittent Malfunction P.00-17).
NO : Repair the connector(s) or wiring harness.
3/24/2023
7 of 16
(5280/MSB22M55001A)
Attached sheet 32
55-104
HEATER, AIR CONDITIONING AND VENTILATION
TROUBLESHOOTING
TROUBLE SYMPTOM CHART
M1554005004001
Trouble symptom
Inspection
procedure No.
Reference page
Communication with the scan tool (M.U.T.-IIISE) is not
possible
1
P.55-104
Cool air does not come
2
P.55-105
The blower does not work
3
P.55-107
The blower air volume cannot be changed
4
P.55-108
The inside/outside air changeover is impossible
5
P.55-110
A/C outlet air temperature cannot be set
6
P.55-112
Air outlets changeover is impossible
7
P.55-114
Ambient temperature sensor system
8
P.55-115
A/C pressure sensor system
9
P.55-116
Blower motor power supply system
10
P.55-117
Heater controller assembly (A/C-ECU) power supply system
11
P.55-118
Heater does not work at all, heater does not work quickly.
12
P.55-120
Cannot communicate with the A/C compressor.
13
P.55-123
The A/C compressor does not stop (runs unintentionally)
14
P.55-125
SYMPTOM PROCEDURES
INSPECTION PROCEDURE 1: Communication with the M.U.T.-IIISE is not possible.
TROUBLESHOOTING HINTS
.
TECHNICAL DESCRIPTION (COMMENT)
If communication with all other systems is not possible, there is a high possibility that there is a malfunction of the diagnosis line. If only the A/C system
cannot communicate with the M.U.T.-IIISE, the
heater controller assembly (A/C-ECU) may be defective.
.

x Malfunction of the heater controller assembly
(A/C-ECU)
x Check and repair the power supply circuit system.
.
DIAGNOSIS
1. Using scan tool (M.U.T.-IIISE), diagnose CAN bus
line.
Electric heater (electric heater-ECU) power supply system
15
Attached sheet 36
When the air conditioning is operating, the air volume becomes lower
than the set air volume and the air volume cannot be changed.
16
Attached sheet 37
3/24/2023
8 of 16
(5280/MSB22M55001A)
Attached sheet 33
HEATER, AIR CONDITIONING AND VENTILATION
TROUBLESHOOTING

IGCT control relay
55-119
STEP 3. Check of open circuit in IG1 line between
ETACS-ECU connector and heater controller assembly
 (A/C-ECU) connector.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to GROUP 00  How
to Use Troubleshooting/Inspection Service Points 
How to Cope with Intermittent Malfunction P.00-17).
NO : Repair the connector(s) or wiring harness.
STEP 4. Measure the voltage at the heater controller
assembly (A/C-ECU) connector.
(1) Disconnect the connector, and measure at the wiring
harness side.
(2) Voltage between B/UP terminal and body ground.
OK: The voltage should measure approximately 12
volts (battery positive voltage).
Q: Is the check result normal?
YES : Go to Step 6.
NO : Go to Step 5.
STEP 5. Check of open circuit in B/UP line between
ETACS-ECU connector and heater controller assembly
(A/C-ECU) connector.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to GROUP 00  How
to Use Troubleshooting/Inspection Service Points 
How to Cope with Intermittent Malfunction P.00-17).
NO : Repair the connector(s) or wiring harness.
STEP 6. Measure the resistance at the heater controller
assembly (A/C-ECU) connector.
(1) Disconnect the connector, and measure at the wiring
harness side.
(2) Resistance between E terminal and body ground
OK: The resistance should be 2 ohms or less
Q: Is the check result normal?
YES : Replace the heater controller assembly (A/C-ECU)
(Refer to P.55-154).
NO : Go to Step 7.
STEP 7. Check of open circuit in E line between heater
controller assembly (A/C-ECU) connector and ground J/C
(DASH) connector.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to GROUP 00  How
to Use Troubleshooting/Inspection Service Points 
How to Cope with Intermittent Malfunction P.00-17).
NO : Repair the connector(s) or wiring harness.
3/24/2023
9 of 16
(5280/MSB22M55001A)
Attached sheet 34
HEATER, AIR CONDITIONING AND VENTILATION
55-99
TROUBLESHOOTING
TROUBLE SYMPTOM CHART
M1554005004001
Trouble symptom
Inspection procedure
No.
Reference page
Communication with the scan tool (M.U.T.-IIISE) is not possible
1
P.55-100
Cool air does not come
2
P.55-100
The blower does not work
3
P.55-102
The blower air volume cannot be changed
4
P.55-104
The inside/outside air changeover is impossible
5
P.55-106
A/C outlet air temperature cannot be set
6
P.55-107
Air outlets changeover is impossible
7
P.55-109
Ambient temperature sensor system
8
P.55-110
A/C pressure sensor system
9
P.55-112
Blower motor power supply system
10
P.55-112
Heater controller assembly (A/C-ECU) power supply system
11
P.55-113
Heater does not work at all, heater does not work quickly.
12
P.55-115
Cannot communicate with the A/C compressor.
13
P.55-118
The A/C compressor does not stop (runs unintentionally)
14
P.55-120
Electric heater (electric heater-ECU) power supply system
15
Attached sheet 36
When the air conditioning is operating, the air volume becomes lower
than the set air volume and the air volume cannot be changed.
16
Attached sheet 37

3/24/2023
10 of 16
(5280/MSB22M55001A)
Attached sheet 35
55-114
HEATER, AIR CONDITIONING AND VENTILATION
TROUBLESHOOTING
STEP 1. Using scan tool (M.U.T.-IIISE), check whether the
other system DTC is set.
Check that the ETACS-ECU has not set a DTC.
CAUTION
To prevent damage to scan tool (M.U.T.-IIISE), always turn
the electric motor switch to the OFF position before connecting or disconnecting scan tool (M.U.T.-IIISE).
(1) Connect scan tool (M.U.T.-IIISE). Refer to "How to connect
the Scan Tool (M.U.T.-IIISE) P.54A-6".
(2) Turn the electric motor switch from OFF position to ON
position.
(3) Check if DTC is set.
(4) Turn the electric motor switch to the OFF position.
Q: Is the DTC set?
YES : Carry out the diagnostic trouble code procedures
(Refer to GROUP 54A - ETACS-ECU, diagnostic
trouble code chart P.54A-505).
NO : Go to Step 2.
STEP 2. Measure the voltage at the heater controller
assembly (A/C-ECU) connector.
(1) Disconnect the connector, and measure at the wiring
harness side.
(2) Power supply mode of the electric motor switch: OFF → ON
(3) Voltage between IG1 terminal and body ground
OK: The voltage should measure approximately 12
volts (battery positive voltage).
Q: Is the check result normal?
YES : Go to Step 4.
NO : Go to Step 3.

IGCT control relay
STEP 3. Check of open circuit in IG1 line between
ETACS-ECU connector and heater controller assembly
 (A/C-ECU) connector.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to GROUP 00 - How to
Use Troubleshooting/Inspection Service Points How to Cope with Intermittent Malfunction P.00-17).
NO : Repair the connector(s) or wiring harness.
STEP 4. Measure the voltage at the heater controller
assembly (A/C-ECU) connector.
(1) Disconnect the connector, and measure at the wiring
harness side.
(2) Voltage between B/UP terminal and body ground.
OK: The voltage should measure approximately 12
volts (battery positive voltage).
Q: Is the check result normal?
YES : Go to Step 6.
NO : Go to Step 5.
3/24/2023
11 of 16
(5280/MSB22M55001A)
Attached sheet 36

INSPECTION PROCEDURE 15: Electric heater (electric heater-ECU) power supply system
TECHNICAL DESCRIPTION (COMMENT)
TROUBLESHOOTING HINTS
If the electric heater (electric heater-ECU) is not
energized, the power supply or ground system to the
ECU may be defective.
 Malfunction of the electric heater (electric
heater-ECU)
 The wiring harness or connectors may have
loose, corroded, or damaged terminals, or terminals pushed back in the connector
DIAGNOSIS
Required Special Tools:
 MB991223: Harness Set
 MB992006: Extra Fine Probe
STEP 1. Measure the voltage at the electric heater (electric
heater-ECU) connector.
(1) Disconnect the connector, and measure at the wiring
harness side.
(2) Power supply mode of the electric motor switch: OFF  ON
(3) Voltage between +12V terminal and body ground
OK: The voltage should measure approximately 12
volts (battery positive voltage).
Q: Is the check result normal?
YES : Go to Step 3.
NO : Go to Step 2.
STEP 2. Check of open circuit in +12V line between IGCT
control relay connector and electric heater (electric
heater-ECU) connector.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to GROUP 00 - How to
Use Troubleshooting/Inspection Service Points How to Cope with Intermittent Malfunction).
NO : Repair the connector(s) or wiring harness.
STEP 3. Measure the resistance at the electric heater
(electric heater-ECU) connector.
(1) Disconnect the connector, and measure at the wiring
harness side.
(2) Resistance between GND terminal and body ground
OK: The resistance should be 2 ohms or less
Q: Is the check result normal?
YES : Replace the electric heater (electric heater-ECU) .
NO : Go to Step 4.
STEP 4. Check of open circuit in GND line between electric
heater (electric heater-ECU) connector and body ground.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to GROUP 00 - How to
Use Troubleshooting/Inspection Service Points How to Cope with Intermittent Malfunction).
NO : Repair the connector(s) or wiring harness.
3/24/2023
12 of 16
(5280/MSB22M55001A)
Attached sheet 37 (1/4)

INSPECTION PROCEDURE 16: When the air conditioning is operating, the air volume becomes
lower than the set air volume and the air volume cannot be changed.
TECHNICAL DESCRIPTION (COMMENT)
If the air volume becomes lower than the set air volume when the air conditioning is operating and the
air volume cannot be changed, a protection control
may have been activated due to the high temperature inside the A/C compressor.
NOTE: Besides the probable causes, the protection
control may also be activated if the air conditioning is
used when all of the following conditions are met:
.
 Ambient temperature: high temperature
 Engine operation status: series hybrid mode, parallel hybrid mode
 Driving condition: low-speed driving,
parked/stopped
 Air conditioning status: high load cooling
TROUBLESHOOTING HINTS
• Clogged condenser fin
• Damage or improper installation of rubber plate
or airguide around the radiator and the condenser
• Damage or improper installation of splash shield
and under cover
• Improper amount of refrigerant
• Malfunction of expansion valve
• Abnormal engine overheating
• Damage or abnormal speed of radiator fan
DIAGNOSIS
Required Special Tools:
 MB991223: Harness Set
 MB992006: Extra Fine Probe
STEP 1. Visually check the rubber plate or the airguide
around the radiator and the condenser for damage and
improper installation.
Q: Is the check result normal?
YES : Go to Step 2
NO : Repair the rubber plate or the airguide around the
radiator and the condenser.
3/24/2023
13 of 16
(5280/MSB22M55001A)
Attached sheet 37 (2/4)

STEP 2. Using scan tool (M.U.T.-IIISE), check whether the
air conditioning or A/C compressor assembly DTC is set.
Check that the diagnostic trouble code related to the air conditioning or A/C compressor assembly is not set.
CAUTION
To prevent damage to scan tool (M.U.T.-IIISE), always turn
the electric motor switch to the "LOCK" (OFF) position
before connecting or disconnecting scan tool
(M.U.T.-IIISE).
(1) Connect scan tool (M.U.T.-IIISE). Refer to "How to connect
the Scan Tool (M.U.T.-IIISE) ."
(2) Turn the electric motor switch from "LOCK" (OFF) position
to "ON" position.
(3) Check the DTC is set.
(4) Turn the electric motor switch to the "LOCK" (OFF) position.
Q: Is the DTC set?
YES : Carry out the diagnosis code procedures.
NO : Go to Step 3
STEP 3. Using scan tool (M.U.T.-IIISE), check actuator test
[The heater controller assembly (A/C-ECU)].
Perform the following actuator test, and check that the A/C
piping solenoid valve works normally.
 Item No. 21: Solenoid valve
Q: Is the check result normal?
YES : Go to Step 11
NO : Go to Step 4
STEP 4. Check the A/C piping solenoid valve assembly.
Refer to Refrigerant Line - Inspection.
Q: Is the check result normal?
YES : Go to Step 5
NO : Replace the A/C piping solenoid valve assembly.
STEP 5. Check the A/C piping solenoid valve relay.
Refer to On-Vehicle Service - Relay Check.
Q: Is the check result normal?
YES : Go to Step 6
NO : Replace the A/C piping solenoid valve relay.
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Attached sheet 37 (3/4)

STEP 6. Measure the voltage at the A/C piping solenoid
valve relay connector.
(1) Disconnect the connector, and measure at the wiring
harness side.
(2) Voltage between power supply terminal and body ground.
OK: The voltage should measure approximately 12
volts (battery positive voltage).
Q: Is the check result normal?
YES : Go to Step 8
NO : Go to Step 7
STEP 7. Check of open and short circuit in power supply
line between fusible link and A/C piping solenoid valve
relay connector.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to GROUP 00 - How to
Use Troubleshooting/Inspection Service Points How to Cope with Intermittent Malfunction).
NO : Repair the connector(s) or wiring harness.
STEP 8. Check of open and short circuit in power supply
line between A/C piping solenoid valve relay connector
and A/C piping solenoid valve connector.
Q: Is the check result normal?
YES : Go to Step 9
NO : Repair the connector(s) or wiring harness.
STEP 9. Check of open circuit in SVLV line between A/C
piping solenoid valve relay connector and heater
controller assembly (A/C-ECU) connector.
Q: Is the check result normal?
YES : Go to Step 10
NO : Repair the connector(s) or wiring harness.
STEP 10. Check of open circuit in ground line between A/C
piping solenoid valve connector and body ground.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to GROUP 00 - How to
Use Troubleshooting/Inspection Service Points How to Cope with Intermittent Malfunction).
NO : Repair the connector(s) or wiring harness.
STEP 11. Diagnosis by refrigerant pressure
Refer to On-Vehicle Service - Diagnosis by Refrigerant
Pressure.
Q: Is the check result normal?
YES : Go to Step 12
NO : Take a necessary action for the A/C system symptom.
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STEP 12. Using scan tool (M.U.T.-IIISE), check actuator test
[The heater controller assembly (A/C-ECU)].
Perform the following actuator test, and check that the blower
works normally.
 Item No. 7: Blower motor
Q: Is the check result normal?
YES : Go to Step 13
NO : Perform Inspection Procedure 4 "The blower air
volume cannot be changed".
STEP 13. Retest the system.
Q: Is the check result normal?
YES : Intermittent malfunction (Refer to GROUP 00 - How to
Use Troubleshooting/Inspection Service Points How to Cope with Intermittent Malfunction).
NO : Replace the heater controller assembly (A/C-ECU).
Then go to Step 14 .
STEP 14. Retest the system.
Q: Is the check result normal?
YES : This diagnosis is complete.
NO : Replace the A/C compressor assembly.
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