Mitsubishi Outlander XL. Manual — part 1182

NO:

Repair or replace the connector. Refer to GROUP 00E,

Harness Connector Inspection P.00E-2.

STEP 4. Check the wiring harness between A/C-ECU
connector C-109 (terminal 9 and 10) and A/C control panel
connector C-119 (terminals 9 and 1).

Q:Is the wiring harness between A/C-ECU connector C-109

(terminal 9 and 10) and A/C control panel connector C-119

(terminals 9 and 1) in good condition?

YES:

Go to Step 5.

NO:

Repair the wiring harness.

STEP 5. 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.00-15.

NO:

Replace the A/C control panel. Then go to Step 6.

STEP 6. 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.00-15.

NO:

Replace the A/C-ECU.

AIR CONDITIONING

55A-19

MANUAL A/C DIAGNOSIS

DTC B1021: Fan Dial SW Error

M15502000943USA0000010000

A/C Control Panel Circuit

A/C-ECU

A/C
CONTROL
PANEL

CPU

INTERFACE
CIRCUIT

ZC600876

Connector: C-109, C-119

C-119

C-109 (B)

0034

DTC SET CONDITION
DTC B1021 will be set when the A/C-ECU cannot
receive the signal of blower knob.

TECHNICAL DESCRIPTION (COMMENT)

Current trouble

｠

The A/C-ECU, the A/C control panel, or connector
(s) or wiring between the two may be defective.

Past trouble

｠

If DTC B1021 is stored as a past trouble, carry out
diagnosis with particular emphasis on wiring and

connector(s) between the A/C-ECU and the A/C
control panel. 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 A/C control panel.

｠

Malfunction of the A/C-ECU.

55A-20

AIR CONDITIONING

MANUAL A/C DIAGNOSIS

DIAGNOSIS

Required Special Tool:

｠

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

｠

MB991824: Vehicle Communication Interface (V.C.I.)

｠

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

｠

MB991910: M.U.T.-III Main Harness A (Vehicles with
CAN communication system)

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. 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.00-15.

NO:

Go to Step 3.

STEP 3. Check A/C control panel connector C-119 and A/C-
ECU connector C-109 for loose, corroded or damaged
terminals, or terminals pushed back in the connector.

Q:Are A/C control panel connector C-119 and A/C-ECU

connector C-109 in good condition?

YES:

Go to Step 4.

AIR CONDITIONING

55A-21

MANUAL A/C DIAGNOSIS

NO:

Repair or replace the connector. Refer to GROUP 00E,

Harness Connector Inspection P.00E-2.

STEP 4. Check the wiring harness between A/C-ECU
connector C-109 (terminal 9 and 10) and A/C control panel
connector C-119 (terminals 9 and 1).

Q:Is the wiring harness between A/C-ECU connector C-109

(terminal 9 and 10) and A/C control panel connector C-119

(terminals 9 and 1) in good condition?

YES:

Go to Step 5.

NO:

Repair the wiring harness.

STEP 5. 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.00-15.

NO:

Replace the A/C control panel. Then go to Step 6.

STEP 6. 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.00-15.

NO:

Replace the A/C-ECU.

55A-22

AIR CONDITIONING

MANUAL A/C DIAGNOSIS