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If DTC B1001 or B1002 is stored as a past trouble, carry out diagnosis with
particular emphasis on wiring and connector(s) between the A/C-ECU and the
interior air temperature sensor. If the connectors 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.
DIAGNOSIS Required Special Tools:
MB991223: Harness Set MB991958: Scan 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)
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
Use scan tool MB991958 to diagnose the CAN bus lines.
1. Connect scan tool MB991958 to the data link connector.
2. Turn the ignition switch to "ON" position.
3. Diagnose the CAN bus line.
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Fig. 10: Connecting Scan Tool MB991958 To Data Link Connector
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Courtesy of MITSUBISHI MOTOR SALES OF AMERICA
.
Q: Is the check result satisfactory?
YES:
Go to Step 2.
NO:
Repair the CAN bus lines (Refer to
CAN COMMUNICATION
SIGNAL TABLE
). 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
HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS
.
NO:
Go to Step 3.
STEP 3. Using scan tool MB991958, check data list item 01: interior
temperature sensor.
1. Connect scan tool MB991958 to the data link connector.
2. Start the engine.
3. Check the data list.
Item 01: Interior temperature sensor.
Check that the ambient tem
perature matches the dis
played value on
CAUTION: To prevent damage to scan tool MB991958,
always turn the ignition switch to the
"LOCK" (OFF) position before connecting or
disconnecting scan tool MB991958.
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the scan tool.
4. Turn the ignition switch to the "LOCK" (OFF) position.
NOTE: When this DTC is set and the system is fail-safe
status, the value of service data displays 20 °C.
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Fig. 11: Connecting Scan Tool MB991958 To Data Link Connector
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Courtesy of MITSUBISHI MOTOR SALES OF AMERICA
.
Q: Is the sensor within the specified range?
YES:
It can be assumed that this malfunction is intermittent. Refer to
HOW TO USE TROUBLESHOOTING/INSPECTION SERVICE POINTS
. Then go to Step 7 .
NO:
Go to Step 4.
STEP 4. Check A/C-ECU connector C-16, C-17 and interior temperature
sensor connector C-120 for loose, corroded or damaged terminals, or
terminals pushed back in the connector
.
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Fig. 12: Identifying Connectors C
-16 & C
-17
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
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Fig. 13: Identifying Connector C
-120
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
Q: Are A/C-ECU connector C-16, C-17 and interior temperature sensor
connector C-120 in good condition?
YES:
Go to Step 5.
NO:
Repair or replace the connector. Refer to
HARNESS
CONNECTOR INSPECTION
. Then go to Step 7 .
STEP 5. Check the wiring harness between A/C-ECU connector C-16
(terminals 20), C-17 (terminals 22) and interior temperature sensor
connector C-120 (terminals 1 and 2)
.
2004 Mitsubishi Endeavor LS
2004 HVAC Automatic Air Conditioning - Endeavor