Ignition MITSUBISHI 380 2005 Workshop Manual

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-68
SYMPTOM CHART M1552009900495
During diagnosis, a DTC code associated with
other system may be set when the ignition switch
is turned on with connector(s) disconnected. On
completion, confirm all systems for DTC code(s).
If DTC code(s) are set, erase them all.
SYMPTOM INSPECTION
PROCEDUREREFERENCE
PA G E
When the ignition switch is "ON", the A/C does not operate. 1.
P.55-69
When the air outlet changeover control knob is moved to DEFROSTER or
DEFROSTER/FOOT position, the A/C or the inside/outside air
changeover damper motor does not operate.2.
P.55-69
Outside/Inside air changeover is not possible. 3.
P.55-70
When the A/C is operating, temperature inside the passenger
compartment does not decrease (cool air is not emitted).4.
P.55-75
Blower fan and motor do not turn. 5.
P.55-89
Blower air amount cannot be changed. 6.
P.55-100
The A/C indicator flashes. 7.
P.55-104
Defogger function does not operate. 8.
P.55-110
Defogger timer function does not operate. 9.
P.55-121
Malfunction of the A/C-ECU power supply system. 10.
P.55-122
Condenser fan does not operate. 11. REFER TO
GROUP 14

SYMPTOM
CHART P.14-3
When sunlight intensity changes, air outlet temperature does not change. 12
P.55-128

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-69
SYMPTOM PROCEDURES
INSPECTION PROCEDURE 1: When the Ignition Switch is "ON", the A/C does not Operate.
.
TECHNICAL DESCRIPTION (COMMENT)
The blower system or the compressor system may
be defective if there is no cool air coming from the
vents.
.
TROUBLESHOOTING HINTS
Malfunction of blower motor
Malfunction of A/C compressor
Refer to component locations GROUP-70
Refer to configuration diagrams GROUP-80
Refer to circuit diagrams GROUP-90
DIAGNOSIS
Check that the blower motor operation when the blower
switch is moved to the "HI" position.
(1) Turn the ignition switch to the "ON" position.
(2) Turn the blower speed selection dial to the blower operating
position.
Q: Does the blower motor operate when the speed
selection dial is turned to the blower operating
position?
YES : Refer to Inspection procedure 4 "When the A/C is
operating, temperature inside the passenger
compartment does not decrease (cool air not emitted)
P.55-75."
NO : Refer to Inspection procedure 5 "Blower fan and
motor do not turn P.55-89."
INSPECTION PROCEDURE 2: When the Air Outlet Changeover Control Knob is Moved to
DEFROSTER or DEFROSTER/FOOT Position, the A/C or the Inside/outside Air Changeover Damper
Motor does not operate.
.
TECHNICAL DESCRIPTION (COMMENT)
If the outside/inside air selection damper control
motor does not operate normally, the inside/outside
air changeover damper motor system may be defec-
tive.
.
TROUBLESHOOTING HINTS
Malfunction of the A/C-ECU
Malfunction of the outside/inside air selection
damper control motor
Damaged harness wires or connectors
Refer to component locations GROUP-70
Refer to configuration diagrams GROUP-80
Refer to circuit diagrams GROUP-90

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-70
DIAGNOSIS
Check operation of the outside/inside air selection damper
control motor.
(1) Turn the ignition switch to the "ON" position.
(2) Outside/inside air selection damper motor switch: This is
used to switch from the inside air to outside air or vice
versa.
(3) Check to see that the outside/inside air selection damper
motor operates normally.
Q: Does outside/inside air selection damper control motor
work normally?
YES : Replace the A/C-ECU.
NO : Refer to Inspection procedure 3, "Inside/outside air
changeover is not possible P.55-70."
INSPECTION PROCEDURE 3: Outside/Inside Air Changeover is not possible.
.
CIRCUIT OPERATION
If the outside/inside air selection damper control
motor does not operate normally, the outside/inside
air selection damper control motor system may be
defective.
.
TROUBLESHOOTING HINTS
Malfunction of the outside/inside air selection
damper control motor
Malfunction of the A/C-ECU
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 defogger and A/C operations.
Q: Do the defogger and A/C work normally?
YES : Go to Step 2.
NO : Refer to Inspection procedure 10 "Malfunction of the
A/C-ECU power supply system P.55-122."

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-71
STEP 2. Check outside/inside air selection damper control
motor connector C-106 for loose, corroded or damaged
terminals, or terminals pushed back in the connector.
Q: Is outside/inside air selection damper control motor
connector C-106 in good condition?
YES : Go to Step 3.
NO : Repair or replace the connector. Refer to GROUP
00E, Harness Connector Inspection P.00E-2. Check
that the outside/inside air selection damper control
motor works normally.
STEP 3. Measure the voltage at outside/inside air selection
damper control motor connector C-106.
(1) Disconnect outside/inside air selection damper control
motor connector C-106, and measure the voltage at the
harness side.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 1 and ground.
The measured value should be approximately 12 volts
(battery positive voltage).
Q: Does the measured voltage correspond with this range?
YES : Go to Step 5.
NO : Go to Step 4.
STEP 4. Check the wiring harness between outside/inside
air selection damper control motor connector C-106
(terminal 1) and the ignition switch (IG2).

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-72
NOTE: Also check junction block connectors C-211(terminal
16) and C-215 (terminal 2) for loose, corroded, or damaged ter-
minals, or terminals pushed back in the connector. If junction
block connector C-211 or C-215 is damaged, repair or replace
the connector as described in GROUP 00E, Harness Connec-
tor Inspection P.00E-2.
Q: Is the wiring harness between outside/inside air
selection damper control motor connector C-106
(terminal 1) and the ignition switch (IG2) in good
condition?
YES : It can be assumed that this malfunction is intermittent.
Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points
How to
Cope with Intermittent Malfunctions P.00-14.
NO : Repair the wiring harness. Check that the
outside/inside air selection damper control motor
works normally.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-76
MB991824: Vehicle Communication Interface (V.C.I.)
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A (Vehicles with CAN
communication system)
STEP 1. Check the defogger and outside/inside air
selection damper control motor operation.
Q: Do the defogger 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 system P.55-122."
STEP 2. Check the blower motor operation.
Q: Does the blower motor work normally?
YES : Go to Step 3.
NO : Refer to Inspection procedure 5, "Front blower fan
and motor do not turn P.55-89."
STEP 3. Check the A/C compressor.
Check the A/C compressor for compressor oil leaks.
Q: Is the check result satisfactory?
YES : Go to Step 4.
NO : Replace the A/C compressor or the expansion valve.
STEP 4. Using scan tool , read the A/C diagnostic trouble
code.
Check if an A/C-ECU DTC is set.
(1) Connect scan tool to the data link connector.
(2) Turn the ignition switch to the "ON" position.
(3) Check if the DTC is set.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?
YES : Go to Step 5.
NO : Refer to DIAGNOSTIC TROUBLE CODE CHART
P.55-9.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-79
STEP 8. Measure the voltage at A/C compressor assembly
connector B-28.
(1) Disconnect A/C compressor assembly connector B-28 and
measure the voltage at the relay box side.
(2) Disconnect powertrain control module connector B-20 and
ground harness side terminal No.6.
(3) Turn the ignition switch to the "ON" position.
(4) A/C compressor assembly connector B-28 terminal 1 and
ground.
The measured value should be approximately 12 volts
(battery positive voltage).
Q: Is the measured voltage approx. 12 volts?
YES : Go to Step 15.
NO : Go to Step 9.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-80
STEP 9. Measure the voltage at A/C compressor clutch
relay connector B-18X.
The top and bottom of the A/C compressor connector are
difficult to identify. Prior to inspection, confirm the triangle
mark on the relay box.
(1) Disconnect A/C compressor connector B-18X and measure
the voltage at the relay box side.
(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 2 and ground.
The measured value should be approximately 12 volts
(battery positive voltage).
Q: Is the measured voltage approx. 12 volts?
YES : Go to Step 11.
NO : Go to Step 10.
STEP 10. Check the wiring harness between A/C
compressor clutch relay connector B-18X (terminal 2) and
the ignition switch (IG2).

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-81
NOTE: Also check intermediate connector A-13, junction block
connectors C-214 and C-215 for loose, corroded, or damaged
terminals, or terminals pushed back in the connector. If inter-
mediate connector A-13, junction block connector C-214 or
C-215 is damaged, repair or replace the connector as
described in GROUP 00E, Harness Connector Inspection
P.00E-2.
Q: Is the wiring harness between A/C compressor clutch
relay connector B-18X (terminal 2) and the ignition
switch (IG2) in good condition?
YES : It can be assumed that this malfunction is intermittent.
Refer to GROUP 00, How to Use
Troubleshooting/Inspection Service Points
How to
Cope with Intermittent Malfunctions P.00-14.
NO : Repair the wiring harness. Check that the air
conditioning works normally.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-85
STEP 16. Measure the voltage at A/C-ECU connector C-15.
(1) Disconnect A/C-ECU connector C-15 and measure the
voltage at the relay box side.
(2) Disconnect powertrain control module connector B-20 and
ground harness side terminal No.6.
(3) Turn the ignition switch to the "ON" position.
(4) Measure the voltage between A/C-ECU connector C-15
terminal No.10 and ground.
The measured value should be approximately 12 volts
(battery positive voltage).
Q: Does the measured voltage correspond with this range?
YES : Go to Step 18.
NO : Go to Step 17.