Mitsubishi Outlander XL. Manual - part 1188

STEP 1. Using scan tool MB991958, diagnose the CAN bus
line

ZC501967

AC404789

ZC5019680000

MB991824

MB991827

MB991910

Data link

connector

To prevent damage to scan tool MB991958, always turn the
ignition  switch  to  the  "LOCK"  (OFF)  position  before
connecting or disconnecting scan tool MB991958.

(1)

Connect scan tool MB991958. Refer to "How to connect the
Scan Tool (M.U.T.-III) P.55A-6."

(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 line. (Refer to GROUP 54D,

Diagnosis P.54D-17).

STEP 2. Using scan tool MB991958 read the ETACS-ECU
diagnostic trouble code.
Check whether an ETACS-ECU DTCs are set or not.

(1)

Turn the ignition switch to the "ON" position.

(2)

Check for ETACS-ECU 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 ETACS-ECU (Refer to GROUP 54Ab,

Diagnostic Trouble Code P.54Ad-8).

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

(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 Step 4.

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.

AIR CONDITIONING

55A-43

MANUAL A/C DIAGNOSIS

Q:Is the check result satisfactory?

YES:

 A poor connection, open circuit or other

intermittent malfunction is present in the lines between
the EATCS-ECU and the A/C-ECU (Refer to GROUP 00E, Harness
Connector Inspection P.00E-2.)

NO:

 Replace the ETACS-ECU. On completion, check that the

DTC is not reset.

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 lines between
the ETACS-ECU and the A/C-ECU (Refer to GROUP 00E, Harness
Connector Inspection P.00E-2.)

NO:

 Replace the A/C-ECU. On completion, check that the

DTC is not reset.

DTC U0151: SRS-ECU Time-out

M15502000950USA0000010000

If DTC U0151 is set in the A/C-ECU, diagnose the
CAN main bus line.

Whenever  the  ECU  is  replaced,  ensure  that  the
communication circuit is normal.

TROUBLE JUDGMENT
The  A/C-ECU  receives  air  conditioning  operation-
related signals from the SRS-ECU via the CAN bus
lines.  If  any  of  the  air  conditioning  control-related
signals  from  the  SRS-ECU  cannot  be  received,  the
diagnostic trouble code U0151 is stored.

TECHNICAL DESCRIPTION (COMMENT)

Current trouble

｠

Connector(s) or wiring harness in the CAN bus lines
between  the  SRS-ECU  and  the  A/C-ECU,  the
power  supply  system  to  the  SRS-ECU,  the  SRS-
ECU itself, or the A/C-ECU may be defective.

Past trouble

｠

If DTC U0151 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  SRS-ECU,  and  the  power  supply
system  to  the  SRS-ECU.  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.

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 GROUP 00, How to Use Troubleshooting/
Inspection Service Points - How to Cope with
Intermittent Malfunctions P.00-15) 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 GROUP 54D,
Explanation about the scan too CAN bus
diagnostics P.54D-10).

TROUBLESHOOTING HINTS

｠

Malfunction of the SRS-ECU

｠

Malfunction of the A/C-ECU

｠

Damaged harness wires and connectors

55A-44

AIR CONDITIONING

MANUAL A/C DIAGNOSIS

DIAGNOSIS

Required Special Tools:

｠

MB991223: Harness Set

｠

MB992006: Extra Fine Probe

｠

MB991958: Scan Tool (M.U.T.-III Sub Assembly)

｠

MB991824: V.C.I.

｠

MB991827: M.U.T.-III USB Cable

｠

MB991910: M.U.T.-III Main Harness A

STEP 1. Using scan tool MB991958, diagnose the CAN bus
line

ZC501967

AC404789

ZC5019680000

MB991824

MB991827

MB991910

Data link

connector

To prevent damage to scan tool MB991958, always turn the
ignition  switch  to  the  "LOCK"  (OFF)  position  before
connecting or disconnecting scan tool MB991958.

(1)

Connect scan tool MB991958. Refer to "How to connect the
Scan Tool (M.U.T.-III) P.55A-6."

(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 line. (Refer to GROUP 54D,

Diagnosis P.54D-17).

STEP 2. Using scan tool MB991958 read the SRS-ECU
diagnostic trouble code.
Check whether an SRS-ECU DTCs are set or not.

(1)

Turn the ignition switch to the "ON" position.

(2)

Check for SRS-ECU 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 SRS-ECU (Refer to GROUP 52B, Diagnostic

Trouble Code P.52B-33).

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.

｠

ETACS-ECU
DTC  indicating  a  time-out  error  related  to  the  SRS-ECU
system

(1)

Turn the ignition switch to the "ON" position.

AIR CONDITIONING

55A-45

MANUAL A/C DIAGNOSIS

(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 Step 4.

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 lines between
the SRS-ECU and the A/C-ECU (Refer to GROUP 00E, Harness
Connector Inspection P.00E-2.)

NO:

 Replace the SRS-ECU. On completion, check that the

DTC is not reset.

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 lines between
the SRS-ECU and the A/C-ECU (Refer to GROUP 00E, Harness
Connector Inspection P.00E-2.)

NO:

 Replace the A/C-ECU. On completion, check that the

DTC is not reset.

DTC U0154: Occupant classification-ECU Time-out

M15502000951USA0000010000

If DTC U0154 is set in the A/C-ECU, diagnose the
CAN main bus line.

Whenever  the  ECU  is  replaced,  ensure  that  the
communication circuit is normal.

TROUBLE JUDGMENT
The  A/C-ECU  receives  the  air  conditioning  control-
related signals from the occupant classification-ECU
via the CAN bus lines. If any of the air conditioning
control-related

 signals

 from

 the

 occupant

classification-ECU cannot be received, the diagnostic
trouble code U0154 is stored.

TECHNICAL DESCRIPTION (COMMENT)

Current trouble

｠

Connector(s) or wiring harness in the CAN bus lines
between the Occupant classification-ECU and the
A/C-ECU, the power supply system to the Occupant
classification-ECU,  the  Occupant  classification-
ECU itself, or the A/C-ECU may be defective.

55A-46

AIR CONDITIONING

MANUAL A/C DIAGNOSIS