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2. Start the engine.
3. Use scan tool MB991958 to run the actuator test.
Item 13: air mix damper motor (FACE position)
Item 14: air mix damper motor (FOOT/FACE position)
Item 15: air mix damper motor (FOOT position)
Item 16: air mix damper motor (DEF/FOOT position)
Item 17: air mix damper motor (DEF position)
Check that the mode selection damper control motor operates.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the sensor within the specified range?
YES:
Replace the A/C-ECU. Then go to Step 7 .
NO:
Go to Step 4.
STEP 4. Check A/C-ECU connector C-16 and mode selection damper
control motor and potentiometer connector C-123 for loose, corroded or
damaged terminals, or terminals pushed back in the connector.
Q: Are A/C-ECU connector C-16 and mode selection damper control
motor and potentiometer connector C-123 in good condition?
YES:
Go to Step 5.
NO:
Repair or replace the connector. Refer to
HARNESS
CONNECTOR INSPECTION
. Then
go to Ste
p 7 .
2004 Mitsubishi Endeavor LS
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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:
The procedure is complete.
NO:
Return to Step 1 .
DTC U1073: BUS OFF TROUBLE JUDGMENT DTC U1073 will be stored when the A/C-ECU ceases CAN communication (bus
off) and then resumes the communication when the ignition switch is turned to the
"LOCK" (OFF) position. TECHNICAL DESCRIPTION (COMMENT) The wiring harness wire or connectors may have loose, corroded, or damage
terminals, or terminals pushed back in the connector, or the A/C-ECU may be
defective. TROUBLESHOOTING HINTS
Defective connector(s) or wiring harness Malfunction of the A/C-ECU
DIAGNOSIS REQUIRED SPECIAL TOOLS:
MB991223: Harness Set
CAUTION: If DTC U1073 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.
2004 Mitsubishi Endeavor LS
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MB991958: Scan Tool (MUT-III Sub Assembly)
MB991824: V.C.I. MB991827: USB Cable MB991910: Main Harness A
STEP 1. Using scan tool MB991958, diagnose the CAN bus line.
1. Connect scan tool MB991958 to the data link connec
tor.
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
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2. Turn the ignition switch to the "ON" position.
3. Diagnose the CAN bus line.
4. Turn the ignition switch to the "LOCK" (OFF) position. Q: Is the CAN bus line found to be normal?
YES:
Go to Step 2.
NO:
Repair the CAN bus lines (Refer to
PRECAUTIONS ON HOW TO
REPAIR THE CAN BUS LINE
).
STEP 2. Recheck for diagnostic trouble code.
Check again if the DTC is set.
1. Connect scan tool MB991958 to the data link connec
tor
2004 Mitsubishi Endeavor LS
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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:
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 A/C-ECU. On completion, check that the DTC is not
reset.
DTC U1100: POWERTRAIN CONTROL MODULE TIME-OUT (RELATED TO ENGINE) TROUBLE JUDGMENT The A/C-ECU receives engine control system-related signal from the powertrain
control module. If the ECU cannot receive the signal, DTC U1100 will be set. TECHNICAL DESCRIPTION (COMMENT)
CURRENT TROUBLE
Connector(s) or wiring harness in the CAN bus lines between the powertrain
control module and the A/C-ECU, the power supply system to the powertrain
control module, the powertrain control module itself, or the A/C-ECU may be
defective.
PAST TROUBLE
If DTC U1100 is stored as a past trouble, carry out diagnosis with particular
emphasis on wiring and connector(s) in the CAN bus line between the A/C-
ECU
and the powe
rtrain
control m
odu
le, and the powe
r supp
ly syste
m to the
CAUTION: If DTC U1100 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.
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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).
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Fig. 99: Connecting Scan Tool MB991958 To Data Link Connector
Courtesy of MITSUBISHI MOTOR SALES OF AMERICA.
2. Turn the ignition switch to the "ON" position.
3. Diagnose the CAN bus line.
4. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the CAN bus line found to be normal?
YES:
Go to Step 2.
NO:
Repair the CAN bus lines (Refer to
PRECAUTIONS ON HOW TO
REPAIR THE CAN BUS LINE
).
2.
STEP 2. Using scan tool MB991958 read the powertrain control module
diagnostic trouble code.
Check whether an engine and automatic transaxle DTCs are set or not.
1. Turn the ignition switch to the "ON" position.
2. Check for engine and automatic transaxle DTCs.
3. Turn the ignition switch to the "LOCK" (OFF) position.
Q: Is the check result satisfactory?
YES:
Go to Step 3.
NO:
Diagnose the powertrain control module (Refer to
DIAGNOSTIC
TROUBLE CODE CHART
).
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3.
STEP 3. Using scan tool MB991958, check for any diagnostic trouble code.Check if a DTC, which relates to CAN communication-linked systems below,
is set.
Combination meter
DTC indicating a time-out error related to the engine or automatic
transaxle control system ETACS-ECU
DTC indicating a time-out error related to the engine or automatic
transaxle control system
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 5 .
NO:
Go to Ste
p 4.
2004 Mitsubishi Endeavor LS
2004 HVAC Heater Air Conditioning, Ventilation - Endeavor