2005 MITSUBISHI 380 air condition

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-106
STEP 3. Check A/C pressure sensor connector A-30 for
loose, corroded or damaged terminals, or terminals
pushed back in the connector.
Q: Is A/C pressure sensor connector A-30 in good
condition?
YES : Go to Step 4.
NO : Repair or replace the connector. Refer to GROUP
00E, Harness Connector Inspection P.00E-2. Check
that the air conditioning works normally.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-107
STEP 4. Check the A/C pressure sensor.
(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
illustration.
(3) Turn ON the engine and then turn ON the air conditioner
switch.
(4) At this time, check to see that the voltage of A/C pressure
sensor terminal No. 2 reflects the specifications of the
figure.
NOTE: The allowance shall be defined as
5%.
Q: Is the A/C pressure sensor in good condition?
YES : Go to Step 5.
NO : Replace the A/C pressure sensor. Check that the air
conditioning works normally.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-108
STEP 5. Check A/C-ECU C-15 and C-16 for loose, corroded
or damaged terminals, or terminals pushed back in the
connector.
Q: Are A/C-ECU C-15 and C-16 in good condition?
YES : Go to Step 6.
NO : Repair or replace the connector. Refer to GROUP
00E, Harness Connector Inspection P.00E-2. Check
that the air conditioning works normally.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-109
STEP 6. Check the wiring harness between A/C-ECU
connector C-15 (terminal 12), C-16 (terminals 34 and 26)
and A/C pressure sensor connector A-30 (terminals 3, 1
and 2).
Q: Is the wiring harness between A/C-ECU connector C-15
(terminal 12), C-16 (terminals 34 and 26) and A/C
pressure sensor connector A-30 (terminals 3, 1 and 2) in
good condition?
YES : Repair the A/C-ECU. Check that the air conditioning
works normally.
NO : Repair the wiring harness. 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 : Replace the A/C-ECU.Check that the air conditioning
works normally.
NO : Correct the refrigerant level (Refer to On-vehicle
ServiceP.55-144). Check that the air conditioning
works normally.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-110
INSPECTION PROCEDURE 8: Defogger Function Does Not Operate.
.
TECHNICAL DESCRIPTION (COMMENT)
If the defogger does not operate when the defogger
switch is turned on, the defogger relay system may
be defective.
.
TROUBLESHOOTING HINTS
Malfunction of the A/C-ECU
Malfunction of the defogger relay
Damaged harness wires or connectors
Refer to component locations GROUP-70
Refer to configuration diagrams GROUP-80
Refer to circuit diagrams GROUP-90
DIAGNOSIS
Required Special Tool:
MB991223: Test Harness Set
STEP 1. Check the A/C and outside/inside air selection
damper control motor operation.
Q: Do the A/C and outside/inside air selection damper
control motor work normally?
YES : Go to Step 2.
NO : Refer to Inspection procedure 10, "Malfunction of the
A/C-ECU power supply systemP.55-122."

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-111
STEP 2. Check defogger relay connector C-201 for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is defogger relay connector C-201 in good condition?
YES : Go to Step 3.
NO : Repair or replace the connector. Refer to GROUP
00E, Harness Connector Inspection P.00E-2. The
defogger system should work normally.
STEP 3. Check the defogger relay continuity.
Follow the table below to check the defogger relay for continu-
ity.
Q: Is the defogger relay in good condition?
YES : Go to Step 4.
NO : Replace the defogger relay. The defogger system
should work normally.
BATTERY VOLTAGE CONNECT
TESTER
BETWEENSPECIFIED
CONDITION
Not applied 4
5 Open Circuit
Connect terminal 1
to the positive
battery terminal
Connect terminal 3
to the negative
battery terminal4
5 Less than 2 ohms

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-112
STEP 4. Check choke coil connector D-11 for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is choke coil connector D-11 in good condition?
YES : Go to Step 5.
NO : Repair or replace the connector. Refer to GROUP
00E, Harness Connector Inspection P.00E-2. The
defogger system should work normally.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-113
STEP 5.Measure the voltage at choke coil connector D-11.
(1) Disconnect connector D-11, and measure the voltage at the
harness side.
(2) Disconnect A/C-ECU connector C-15 and ground harness
side terminal No.27.
(3) Turn the ignition switch to the "ON" position.
(4) Measure the voltage between choke coil connector D-11
terminal No.1 and ground.
The measured value should be approximately 12 volts.
Q: Is the measured voltage approx. 12 volts?
YES : Go to Step 13.
NO : Go to Step 6.