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To prevent damage to diagnostic tool , always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting diagnostic tool .
1. Connect the diagnostic tool to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Select "Interactive Diagnosis" from the start-up screen.
4. Select "System Select."
5. Choose "AUTO A/C" from the "BODY" tab.
6. Select "MITSUBISHI."
7. Select "Data List."
8. Choose an appropriate item and select the "OK" button.
HOW TO PERFORM ACTUATOR TEST
Required Special Tools:
: Diagnostic Tool (MUT-III Sub Assembly)
MB991824: Vehicle Communication Interface (V.C.I.)
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A (Vehicles with CAN
communication system)
To prevent damage to diagnostic tool , always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting diagnostic tool .
1. Connect the diagnostic tool to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Select "Interactive Diagnosis" from the start-up screen.
4. Select "System Select."
5. Choose "AUTO A/C" from the "BODY" tab.
6. Select "MITSUBISHI."
7. Choose "Actuator Test" from "AUTO A/C" screen.
8. Choose an appropriate item and select the "OK" button.
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HOW TO DIAGNOSE THE CAN BUS LINE
Required Special Tools:
: Diagnostic Tool (MUT-III Sub Assembly)
MB991824: Vehicle Communication Interface (V.C.I.)
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A
To prevent damage to diagnostic tool , always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting diagnostic tool .
1. Connect diagnostic tool to the data link connector.
2. Turn the ignition switch to the "ON" position.
3. Select "CAN bus diagnosis" from the start-up screen.
4. When the vehicle information is displayed, confirm that it
matches the vehicle whose CAN bus lines will be
diagnosed.
If they match, go to step 8.
If not, go to step 5.
5. Select "view vehicle information" button.
6. When the vehicle information is displayed, confirm again
that it matches the vehicle which is diagnosed CAN bus line.
If they match, go to step 8.
If not, go to step 5.
7. Press the "OK" button.
8. When the options are displayed, choose the options (mark
the check) and then select "OK".
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DIAGNOSTIC TROUBLE CODE CHART M1554004900214
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 of repairs, confirm all systems for
DTC code(s). If DTC code(s) are set, erase them
all.
DIAGNOSTIC
TROUBLE CODE
NO.DIAGNOSTIC ITEM REFERENCE
PA G E
B1001 Interior temperature sensor system (short circuit)
P.55-10
B1002 Interior temperature sensor system (open circuit)
P.55-10
B1011 Ambient air temperature sensor system (short circuit)
P.55-16
B1012 Ambient air temperature sensor system (open circuit)
P.55-16
B1021 Air thermo sensor system (short circuit)
P.55-22
B1022 Air thermo sensor system (open circuit)
P.55-22
B1041 Air mixing damper control motor and potentiometer (potentiometer
system shorted to its power supply)P.55-28
B1042 Air mixing damper control motor and potentiometer (potentiometer
system shorted to its ground)P.55-28
B1045 Air mixing damper control motor and potentiometer (activating
system failure)P.55-35
B1061 Mode selection damper control motor and potentiometer
(potentiometer system shorted to its power supply)P.55-41
B1062 Mode selection damper control motor and potentiometer
(potentiometer system shorted to its ground)P.55-41
B1065 Mode selection damper control motor and potentiometer (activating
system failure)P.55-48
U1073 Bus off
P.55-54
U1100
Electronic control unit time-out (related to engine)P.55-56
U 1111 M u l t i - c e n t e r d i s p l a y u n i t ( m i d d l e g r a d e t y p e ) t i m e - o u t
P.55-60
U1120 Failure information on Electronic control unit (related to engine)
P.55-64
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DIAGNOSTIC TROUBLE CODE PROCEDURES
DTC B1001, B1002: Interior Temperature Sensor System.
DTC SET CONDITION
DTC B1001 is set if there is a short circuit in the
interior temperature sensor input circuit.
DTC B1002 is set if there is a defective connector
connection, or if there is an open circuit in the
harness.
.
TECHNICAL DESCRIPTION (COMMENT)
Current trouble
The A/C-ECU, the interior air temperature sensor,
or connector(s) or wiring between the two may be
defective.Past trouble
If DTC B1001 or B1002 is stored as a past trou-
ble, carry out diagnosis with particular emphasis
on wiring and connector(s) between the A/C-ECU
and the interior air temperature sensor. If the con-
nectors and wiring are normal, and obviously the
ECU is the cause of the trouble, replace the ECU.
If in doubt, do not replace the ECU.
.
TROUBLESHOOTING HINT
Malfunction of connector.
Malfunction of the harness.
Malfunction of the interior temperature sensor.
Malfunction of the A/C-ECU.
Refer to component locations GROUP-70
Refer to configuration diagrams GROUP-80
Refer to circuit diagrams GROUP-90
DIAGNOSIS
Required Special Tool:
: Diagnostic Tool (MUT-III Sub Assembly)
MB991824: Vehicle Communication Interface (V.C.I.)
MB991827: MUT-III USB Cable
MB991910: MUT-III Main Harness A (Vehicles with CAN
communication system)
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STEP 1. Using diagnostic tool , diagnose the CAN bus line.
Use diagnostic tool to diagnose the CAN bus lines.
(1) Connect diagnostic tool to the data link connector.
(2) Turn the ignition switch to "ON" position.
(3) Diagnose the CAN bus line.
Q: Is the check result satisfactory?
YES : Go to Step 2.
NO : Repair the CAN bus lines. (Refer to GROUP 54C,
Diagnosis-CAN Bus Diagnostic Chart P.54C-405).
Then go to Step 7.
STEP 2. Recheck for diagnostic trouble code.
Recheck if the DTC is set.
(1) Erase the DTC.
(2) Turn the ignition switch to "ON" position.
(3) Check if the DTC is set.
Q: Is the check result satisfactory?
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 : Go to Step 3.
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STEP 3. Using diagnostic tool , check data list item 59:
Inside temperature sensor.
To prevent damage to diagnostic tool , always turn the
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting diagnostic tool .
(1) Connect diagnostic tool to the data link connector.
(2) Start the engine.
(3) Set diagnostic tool to the data reading mode for item 59:
Inside temperature sensor.
Check that the interior temperature matches the dis-
played value on the diagnostic tool.
NOTE: When this DTC is set and the system is in fail-safe
status, the value of service data displays 25
C.
(4) Turn the ignition switch to the "LOCK" (OFF) position.
Q: Does the interior temperature match the displayed value
on the diagnostic tool?
YES : Replace the A/C-ECU. Then go to Step 7.
NO : Go to Step 4.
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STEP 4. Check A/C-ECU connector C-15, C-16 and interior
temperature sensor connector C-123 for loose, corroded
or damaged terminals, or terminals pushed back in the
connector.
Q: Are A/C-ECU connectors C-15, C-16 and interior
temperature sensor connector C-123 in good condition?
YES : Go to Step 5.
NO : Repair or replace the connector. Refer to GROUP
00E, Harness Connector Inspection P.00E-2. Then go
to Step 7.
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STEP 5. Check the wiring harness between A/C-ECU
connector C-15 (terminals 20), C-16 (terminals 22) and
interior temperature sensor connector C-123 (terminals 1
and 2).
Q: Are the wiring harnesses between A/C-ECU connector
C-15 (terminals 20), C-16 (terminals 22) and interior
temperature sensor connector C-123 (terminals 1 and 2)
in good condition?
YES : Go to Step 6.
NO : Repair the wiring harness. Then go to Step 7.