air conditioning MITSUBISHI 380 2005 Workshop Manual

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-132
STEP 5. Check the wiring harness between photo sensor
connector C-04 (terminals 3, 4) and A/C-ECU connector
C-15 (terminal 19), C-16 (terminal 25).
Q: Is the wiring harness between photo sensor connector
C-04 (terminals 3, 4) and A/C-ECU connector C-15
(terminal 19), C-16 (terminal 25) in good condition?
YES : Go to Step 6.
NO : Repair the wiring harness. Check that the air
conditioning works normally.
STEP 6. Replace the photo sensor.
Q: Does the A/C operate normally?
YES : No action is necessary and testing is complete.
NO : Replace the A/C-ECU. Check that the air conditioning
works normally.
STEP 7. Check the refrigerant level.
Use the refrigerant recovery station to remove all of the refrig-
erant, and then calculate the amount of the refrigerant and
charge it.
Q: Is the refrigerant level correct?
YES : Refer to GROUP 55A, Symptom Chart P.55-68.
NO : Correct the refrigerant level. Check that the air
conditioning works normally. (Refer to GROUP 55A
On-vehicle Service P.55-141).

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-133
DATA LIST REFERENCE TABLEM1554005100136
MUT-III
DIAGNOSTIC
TOOL DISPLAYITEM
NO.INSPECTION ITEM INSPECTION REQUIREMENT NORMAL VALUE
Inside
temperature
sensor59 Interior temperature
sensorIgnition switch: ON Inside air
temperature and
temperature
displayed on the
diagnostic tool are
identical.
Outside
temperature
sensor58 Outside temperature
sensorIgnition switch: ON Outside air
temperature and
temperature
displayed on the
diagnostic tool are
identical.
Air thermo sensor 20 Air thermo sensor Ignition switch: ON The temperature
measured behind
the evaporator
matches the
displayed value on
the diagnostic tool
while the engine is
cold.
Pressure sensor 61 A/C pressure sensor Ignition switch: ON Measured refrigerant
pressure is nearly
equal to the value
shown on the
diagnostic tool
(MPa).
Water
temperature
sensor62 Engine coolant
temperature sensor
(Data received by
CAN
Communication)Ignition switch: ON Engine coolant
temperature and
temperature
displayed on the
diagnostic tool are
identical.
Photo sensor 67 Photo sensor Ignition switch: ON Amount of light is
proportional to
voltage displayed on
the diagnostic tool.
Air mix
potentiometer63 Air mixing damper
control motor
potentiometerIgnition switch: ON Damper
positionOpening degree (V)
MAX. HOT Approx. 5
MAX. COOL Approx. 0
Air mix
potentiometer
(Target)64 Target value for air
mixing damper
control motor
potentiometerIgnition switch: ON Damper
positionOpening degree (V)
MAX. HOT Approx. 5
MAX. COOL Approx. 0

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-134
Air outlet c/o
potentiometer55 Mode selection
damper control
motor potentiometerIgnition switch: ON Damper
positionOpening degree (V)
FA C E A p pr o x . 5
FOOT Approx. 3.75
FOOT/DEF. Approx. 2.5
DEF. Approx. 1.75
Air outlet c/o
potentiometer
(target)56 Target value for
mode selection
damper control
motor potentiometerIgnition switch: ON Damper
positionOpening degree (V)
FA C E A p pr o x . 5
FOOT Approx. 3.75
FOOT/DEF. Approx. 2.5
DEF. Approx. 1.75
In/out air
changeover
damper motor65 Outside/inside air
selection damper
control motorIgnition switch: ON Damper set
positionDamper position
Fresh air
positionFRESH
Air recirculation
positionRECIRC
Front blower fan 68 Blower motor Ignition switch: ON The actual air
volume (blower
motor speed)
corresponds to the
air volume shown on
the diagnostic tool.
Front blower
motor voltage 71 Blower motor Ignition switch: ON The air volume set
by the heater control
corresponds to the
value shown on the
diagnostic tool. (V)
Air conditioning
switch state1 Air conditioning
switchIgnition switch: ON Air conditioning
switch: ONDiagnostic tool
indication: "pressed"
Air conditioning
switch: OFFDiagnostic tool
indication: "release"
Rear defogger
switch state7 Rear window
defogger switchIgnition switch: ON Rear window
defogger
switch: ONDiagnostic tool
indication: "pressed"
Rear window
defogger
switch: OFFDiagnostic tool
indication: "release"
Refrigerant
pressure73 Refrigerant pressure Ignition switch: ON The diagnostic tool
indication is normal MUT-III
DIAGNOSTIC
TOOL DISPLAYITEM
NO.INSPECTION ITEM INSPECTION REQUIREMENT NORMAL VALUE

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-135
Temperature
setting23 Temperature setting
actualIgnition switch: ON The actual setting
corresponds with
diagnostic tool
display.
Vehicle speed 26 Actual vehicle speed Ignition switch: ON The vehicle speed
corresponds with
diagnostic tool
display.
A/C compressor
drive request27 Compressor clutch Engine: ON
Compressor:
ONDiagnostic tool
indication: "ON"
Compressor:
OFFDiagnostic tool
indication: "OFF"
Illumination 15 Display lighting Ignition switch: ON
Lights: ON
Diagnostic tool
indication: "ON"
Lights: OFF
Diagnostic tool
indication: "OFF"
Engine speed 23 Actual engine speed Engine: ON The engine speed
corresponds with
diagnostic tool
display.
In/out air select
switch state3 In/out air select
switch Ignition switch: ON In/out air
switch: ONDiagnostic tool
indication: "pressed"
In/out air
switch: OFFDiagnostic tool
indication: "release"
Rear defogger
relay72 Rear defogger relay Ignition switch: ON
Rear defogger:
ONDiagnostic tool
indication: "ON"
Rear defogger:
OFFDiagnostic tool
indication: "OFF" MUT-III
DIAGNOSTIC
TOOL DISPLAYITEM
NO.INSPECTION ITEM INSPECTION REQUIREMENT NORMAL VALUE

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-136
ACTUATOR TEST REFERENCEM1554005200133
MUT-III DIAGNOSTIC
TOOL DISPLAYITEM NO. INSPECTION ITEM DRIVE CONTENT
Blower fan: OFF 83 Blower motor OFF
Blower fan: Middle 84 Middle speed
Blower fan: High 85 High speed
Air mix damper motor:
0%42 Air mixing damper control motor Opening degree: approx.
0% (Max cool)
Air mix damper motor:
100%43 Opening degree: approx.
100% (Max hot)
Air outlet c/o damper:
FA C E70 Mode selection damper control
motorFA C E
Air outlet c/o damper: Bi_
Level67 FOOT/FACE
Air outlet c/o damper:
FOOT71 FOOT
Air outlet c/o damper:
DEF/FOOT69 DEF/FOOT
Air outlet c/o damper:
DEF68 DEF
Idle up request: high load 74 Idle speed HIGH idle up
Idle up request: low load 75 LOW idle up
Idle up request: OFF 76 OFF
Rear defogger switch:
OFF40 Rear window defogger switch Rear window defogger: OFF
Rear defogger switch:
ON41 Rear window defogger: ON
Idle up request: OFF 50 Idle up operation Idle up: OFF
Idle up request: low load 51 Idle up: low load
Idle up request: high load 52 Idle up: high load
Condenser: 0% 77 Condenser fan OFF
Condenser: 50% 79 Middle speed
Rheostat: 0% 80 Rheostat- Illumination control OFF
Rheostat: 100% 81 Full duty
Rheostat: 50% 82 Half duty

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-137
CHECK AT A/C-ECU TERMINALM1552010300572
TERMINAL
NO.CHECK ITEM CHECKING REQUIREMENTS NORMAL CONDITION
1 Air mixing damper control motor When the air mix damper is
moved to the MAX. COOL
position. 10 V
When the air mix damper is
moved to the MAX. HOT
position. 0.5 V
2 Air mixing damper control motor When the air mix damper is
moved to the MAX. COOL
position. 0.5 V
When the air mix damper is
moved to the MAX. HOT
position. 10 V
3 Back-up power supply Always Battery positive voltage
4 Mode selection damper control
motor (DEF)When the damper is moved to
the FACE position. 0.5 V
When the damper is moved to
the DEF position. 10 V
5 Outside/inside air selection
damper control motor (outside)When the damper is moved to
the inside air recirculation
position.0.5 V
When the damper is moved to
the outside air induction
position.0 V (when the motor is
stopped)
6 Outside/inside air selection
damper control motor (inside)When the damper is moved to
the inside air recirculation
position.0 V (when the motor is
stopped)
When the damper is moved to
the outside air induction
position.0.5 V
8 Rear defogger relay Ignition switch: ON Battery positive voltage
9 Front blower relay Ignition switch: ON Battery positive voltage
10 A/C compressor relay A/C compressor relay: ON Battery positive voltage
11 Mode selection damper control
motor (FACE)When the damper is moved to
the FACE position. 10 V
When the damper is moved to
the DEF position. 0.5 V
12 A/C pressure sensor Ignition switch: ON 5 V

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-138
16 Potentiometer power supply Ignition switch: ON 5 V
17 Power transistor (BASE) When the blower speed
selection dial shows Maximum
air volume.1 V
18 Power transistor
(COLLECTOR)When the blower speed
selection dial shows Maximum
air volume.12.1 V
19 Photo sensor Ignition switch: ON 5 V
20 Sensors and potentiometers
groundAlways 0 V
21 Mode selection damper control
motor potentiometer inputWhen the damper is moved to
the FACE position. 4 V
22 Interior temperature sensor Ignition switch: ON 5 V
23 Ambient temperature sensor
inputWhen sensor temperature is
25
C (77F) [4 k]1.9 V
24 Air thermo sensor input When sensor temperature is
25
C (77F) [1.5 k]2.2 V
25 Photo sensor ground Ignition switch: ON 0 V
26 A/C pressure sensor at 2.6 MPa 3.9 V
27 Ground Always 0 V
28 Power supply to the ignition
switch (IG2)Ignition switch: ON Battery positive voltage
29 Air mixing damper control motor
potentiometer inputWhen the damper door is
moved to the MAX. HOT
position.1.4 V
30 Illumination ground Always 0 V
31 ILL power supply Lighting switch: ON Battery positive voltage
34 A/C pressure sensor ground Always 0 V
36 Power supply to the ignition
switch (ACC)Ignition switch: ON Battery positive voltage TERMINAL
NO.CHECK ITEM CHECKING REQUIREMENTS NORMAL CONDITION

SPECIAL TOOLS
HEATER, AIR CONDITIONING AND VENTILATION55-139
SPECIAL TOOLSM1552000600334
TOOL TOOL NUMBER
AND NAMESUPERSESSION APPLICATION
MB991367
Special spannerMB991367-01 Armature mounting nut of
compressor removal and
installation
MB991386 Pin MIT217213 Armature mounting nut of
compressor removal and
installation
MB991658
Test harness setTool not available Inspection of throttle position
sensor

SPECIAL TOOLS
HEATER, AIR CONDITIONING AND VENTILATION55-140
A: MB991824
B: MB991827
C: MB991910
D: MB991911
E: MB991914
F: MB991825
G: MB991826
MUT-III Sub
Assembly
A: Vehicle
communicatio
n interface
(V.C.I.)
B: MUT-III USB
cable
C: MUT-III main
harness A
(Vehicles with
CAN
communicatio
n system)
D: MUT-III main
harness B
(Vehicles
without CAN
communicatio
n system)
E: MUT-III main
harness C (for
Daimler
Chrysler
models only)
F: MUT-III
measurement
adapter
G: MUT-III
Trigger
HarnessMB991824-KIT
NOTE: . G:
MB991826 MUT-III
Trigger Harness is not
necessary when
pushing V.C.I.
ENTER key.Checking diagnostic trouble codes
For vehicles with CAN
communication, use MUT-III
main harness A to send
simulated vehicle speed. If you
connect MUT-III main harness B
instead, the CAN
communication does not
function correctly. TOOL TOOL NUMBER
AND NAMESUPERSESSION APPLICATION

ON-VEHICLE SERVICE
HEATER, AIR CONDITIONING AND VENTILATION55-141
ON-VEHICLE SERVICE
REFRIGERANT LEVEL TESTM1552008400408
Use the refrigerant recovery station to remove all of the refrig-
erant, and then calculate the amount of the refrigerant and
charge it.
A/C COMPRESSOR CLUTCH TESTM1552019900032
1. Disconnect the air conditioning compressor clutch connector
to the air conditioning compressor clutch.
2. Connect positive battery voltage directly to the connector for
the air conditioning compressor clutch.
3. If the air conditioning compressor clutch is normal, there will
be a "click." If the pulley and armature do not make contact
("no click"), there is a malfunction.
SIMPLE INSPECTION OF THE A/C PRESSURE
SENSOR
M1552014700118
1. Assemble a gauge manifold on the high pressure service
valve.
2. Disconnect the A/C pressure sensor connector and connect
special tool test harness MB991658 as shown in the illustra-
tion.
3. Turn ON the engine and then turn ON the air conditioner
switch.