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powertrain control module. 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 HINTS
Powertrain control module failed Malfunction of the A/C-ECU Damaged harness wires and connectors
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)
1.
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
NOTE: For a past trouble, you cannot find it by the scan tool CAN
bus diagnostics even if there is a failure in CAN bus lines.
In this case, refer to HOW TO USE TROUBLESHOOTING/
INSPECTION SERVICE POINTS
) and check the CAN bus
lines. You can narrow down the possible cause of the
trouble by referring to the DTC, which is set regarding the
CAN communication-linked ECUs (Refer to EXPLANATION
ABOUT THE MUT
-III CAN BUS DIAGNOSIS
).
CAUTION: To prevent damage to scan tool (MUT-III), always
turn the ignition switch to the "LOCK" (OFF)
position before connecting or disconnecting
scan tool (MUT-III).
2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor
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NO:
Replace the A/C-ECU. On completion, check that the DTC is not
reset.
DTC U1111: MULTI-CENTER DISPLAY UNIT (MIDDLE GRADE TYPE) TIME-OUT TROUBLE JUDGMENT The A/C-ECU receives signals from the multi-center display unit (middle grade
type). If the ECU cannot receive the signal related to the multi-center display unit,
DTC U1111 will be set. TECHNICAL DESCRIPTION (COMMENT)
CURRENT TROUBLE
Connector(s) or wiring harness in the CAN bus lines between the A/C-ECU
and the middle-grade multi-center display unit, the power supply system to the
display unit, the display unit itself, or the A/C-ECU may be defective.
PAST TROUBLE
When DTC U1111 is set as a past trouble, carry out diagnosis with particular
emphasis on connector(s) or wiring harness in the CAN bus lines between the
A/C-ECU and the middle-grade multi-center display unit, the power supply
system to the display unit. If the connectors and wiring are normal, and
obviously the ECU or the middle-grade multi-center display is the cause of the
trouble, replace the ECU or the middle-grade multi-center display. If in doubt,
do not replace the ECU or the display unit.
CAUTION: If DTC U1111 is set in the A/C-ECU, diagnose the
CAN main bus line.
CAUTION: Whenever the ECU is replaced, ensure that the
communication circuit is normal.
NOTE: For a past trouble, you cannot find it by the scan tool CAN
bus diagnostics even if there is a failure in the CAN bus
lines. In this case, refer to HOW TO USE
TROUBLESHOOTING/ INSPECTION SERVICE POINTS
). and
2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor
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Check if a DTC, which relates to CAN communication-linked systems below,
is set.
ETACS-ECU
DTC indicating a time-out error of middle-grade multi-center display unit
1. Turn the ignition switch to the "ON" position.
2. Check for a DTC related to the relevant system.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?
YES:
Go to Step 4.
NO:
Go to Step 5 .
STEP 4. Recheck for diagnostic trouble code.
Check again if the DTC is set.
1. Turn the ignition switch to the "ON" position.
2. Check if the DTC is set.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?
YES:
A poor connection, open circuit or other intermittent malfunction is
present in the CAN bus lines between the middle-grade multi-center
display unit and the A/C-ECU (Refer to
HOW TO USE
TROUBLESHOOTING/ INSPECTION SERVICE POINTS
).
NO:
Replace the A/C-ECU. On completion, check that the DTC is not
reset.
2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor
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STEP 5. Recheck for diagnostic trouble code.
Check again if the DTC is set.
1. Turn the ignition switch to the "ON" position.
2. Check if the DTC is set.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?
YES:
A poor connection, open circuit or other intermittent malfunction is
present in the CAN bus lines between the middle-grade multi-center
display unit and the A/C-ECU (Refer to
HOW TO USE
TROUBLESHOOTING/ INSPECTION SERVICE POINTS
).
NO:
Replace the middle-grade multi-center display unit. On completion,
check that the DTC is not reset.
2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor
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TROUBLESHOOTING HINTS
Malfunction of the A/C-ECU. Malfunction of the powertrain control module.
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.
1. Connect scan tool MB991958 to the data link connec
tor.
In this case, refer to HOW TO USE TROUBLESHOOTING/ INSPECTION SERVICE POINTS
). and check the CAN bus
lines. You can narrow down the possible cause of the
trouble by referring to the DTC, which is set regarding the
CAN communication-linked ECUs (Refer to EXPLANATION
ABOUT THE MUT
-III CAN BUS DIAGNOSIS
).
CAUTION: To prevent damage to scan tool (MUT-III), always
turn the ignition switch to the "LOCK" (OFF)
position before connecting or disconnecting
scan tool (MUT-III).
2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor
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Check again if the DTC is set.
1. Turn the ignition switch to the "ON" position.
2. Check if the DTC is set.
3. Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the check result satisfactory?
YES:
There is an intermittent malfunction such as poor engaged connector
(s) or open circuit (Refer to
HOW TO USE TROUBLESHOOTING/
INSPECTION SERVICE POINTS
).
NO:
Replace the powertrain control module. On completion, check that
the DTC is not reset.
STEP 5. Recheck for diagnostic trouble code.
2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor
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Check again if the DTC is set.
1. Turn the ignition switch to the "ON" position.
2. Check if the DTC is set.
3. Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the check result satisfactory?
YES:
A poor connection, open circuit or other intermittent malfunction is
present in the lines between the powertrain control module and the A/C-
ECU (Refer to
HOW TO USE TROUBLESHOOTING/ INSPECTION
SERVICE POINTS
).
NO:
Replace the A/C-ECU. On completion, check that the DTC is not
reset.
SYMPTOM CHART
CAUTION: 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.
2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor
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HOW TO USE TROUBLESHOOTING/ INSPECTION SERVICE POINTS
.
NO:
Repair the wiring harness. Check that the outside/inside air selection
damper control motor works normally.
Fig. 123: Locating Connector C
-103
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor