2005 MITSUBISHI 380 Ignition

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.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-91
STEP 2. Measure the voltage at blower motor connector
C-115.
(1) Disconnect blower motor connector C-115, and measure
the voltage at the wiring harness side.
(2) Disconnect A/C-ECU connector C-15 and ground harness
side terminal No.9.
(3) Turn the ignition switch to the "ON" position.
(4) Measure the voltage between C-115 (terminal 1) and
ground.
The measured value should be approx. 12 volts (battery
positive voltage).
Q: Is the measured voltage approx. 12 volts?
YES : Go to Step 11.
NO : Go to Step 3.
STEP 3. Check blower relay connector C-202 for loose,
corroded or damaged terminals, or terminals pushed back
in the connector.
Q: Is blower relay connector C-202 in good condition?
YES : Go to Step 4.
NO : Repair or replace the connector. Refer to GROUP
00E, Harness Connector Inspection P.00E-2.The
blower motor should operate normally.

AUTO A/C DIAGNOSIS
HEATER, AIR CONDITIONING AND VENTILATION55-92
STEP 4. Check the blower relay continuity.
Follow the table below to check the blower relay for continuity.
Q: Is the blower relay continuity in good condition?
YES : Go to Step 5.
NO : Replace the blower relay. The blower motor should
operate normally.
STEP 5. Measure the voltage at blower relay connector
C-202.
(1) Disconnect blower relay connector C-202, and measure the
voltage at the junction block 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: Is the measured voltage approx. 12 volts?
YES : Go to Step 7.
NO : Go to Step 6. BATTERY
VOLTAGETESTER
CONNECTIONSPECIFIED
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