Mitsubishi 380. Manual - part 963

ANTI-LOCK BRAKING SYSTEM (ABS) DIAGNOSIS

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-77

STEP 3. Measure the resistance at ABS-ECU connector 
A-02.
(1) Disconnect the connector A-02, and use special tool 

Inspection Check Harness (MB991219) to probe the wiring 
harness-side connector.

NOTE: The special tool (Inspection test harness) 
MB991219 for connector pin contact pressure should be 
used. The test probe should never be forcibly inserted, as it 
may cause a defective contact.

(2) Measure the resistance between terminal 1, 4 and ground. 

It should be 2 ohms or less.

Q: Is the measured resistance 2 ohms or less?

YES : Go to Step 5.
NO :  Go to Step 4.

STEP 4. Check ABS-ECU connector A-02  for loose, 
corroded or damaged terminals, or terminals pushed back 
in the connector.
Q: Is ABS-ECU connector A-02 damaged?

YES : Repair or replace the damaged component(s). Refer 

to GROUP 00E, Harness Connector Inspection 

P.00E-2

. Then go to Step 8.

NO :  An open circuit may be present in the ground circuit. 

Repair the wiring harness between ABS-ECU 
connector A-02 terminals 1, 4 and the body ground. 
Then go to Step 8.

STEP 5. Check the battery.
Check the battery (Refer to GROUP 54A, Battery test 

P.54A-6

).

Q: Is the battery in good condition?

YES : Go to Step 6.
NO :  Charge or replace the battery. Then go to Step 8.

35DB098A

CONNECTOR: A-02

HYDRAULIC UNIT

(WITH BUILT-IN ABS-ECU)

TEST 

HARNESS

(MB991219)

16DB402A

A-02 (GR)

CONNECTOR: A-02 

A-02 HARNESS CONNECTOR:

ANTI-LOCK BRAKING SYSTEM (ABS) DIAGNOSIS

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-78

STEP 6. Check the charging system.
Check the charging system (Refer to GROUP 16, Charging 
system diagnosis 

P.16-3

).

Q: Is the charging system in good condition?

YES : Go to Step 7.
NO :  Repair or replace the charging system 

component(s).Then go to Step 8.

STEP 7. Retest the system.

Q: Can the ABS-ECU communicate with the diagnostic tool 

(MUT-III Sub Assembly)?
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 Malfunction 

P.00-14

.

NO :  Replace the ABS-ECU. Then go to Step 8.

STEP 8. Retest the system.

Q: Can the ABS-ECU communicate with the diagnostic tool 

(MUT-III Sub Assembly)?
YES : The procedure is complete.
NO :  Go to Step 1.

ANTI-LOCK BRAKING SYSTEM (ABS) DIAGNOSIS

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-79

INSPECTION PROCEDURE 3: When the Ignition Key is Turned to "ON" (Engine Stopped), the 
BRAKE/ABS Warning Light does not Illuminate. INSPECTION PROCEDURE 4: The BRAKE/ABS 
Warning Light Remains Illuminated after the Engine is Started.

.

TECHNICAL DESCRIPTION (COMMENT)

• The ABS-ECU sends the ABS warning light and 

the brake warning light signals to the combination 
meter via the CAN communication.

• This may be caused by faults in the CAN bus line, 

the combination meter, or the ABS-ECU.

.

TROUBLESHOOTING HINTS (The most 
likely causes for this case:) 

• Damaged wiring harness or connector

• Combination meter defective 

• Malfunction of the hydraulic unit (integrated with 

ABS-ECU)

Circuit drawings

• Refer to circuit diagrams GROUP-

90

• Refer to configuration diagrams GROUP-

80

.

DIAGNOSIS

Required Special Tools:

• MB991958: Diagnostic Tool (MUT-III Sub Assembly)

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

• MB991827: MUT-III USB Cable

• MB991910: MUT-III Main Harness A

.

35DB090A

A

ANTI-LOCK BRAKING SYSTEM (ABS) DIAGNOSIS

ANTI-LOCK BRAKING SYSTEM (ABS)

35B-80

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

CAUTION

To prevent damage to diagnostic tool MB991958, always 
turn the ignition switch to the "LOCK" (OFF) position 
before connecting or disconnecting diagnostic tool 
MB991958.
Use diagnostic tool MB991958 to diagnose the CAN bus lines.
(1) Connect diagnostic tool MB991958 to the data link 

connector.

(2) Turn the ignition switch to the "ON" position.
(3) Diagnose the CAN bus line.

Q: Is the check result satisfactory?

YES : Go to Step 2.
NO :  Repair the CAN bus lines (Refer to GROUP 54C, 

Diagnosis-CAN Bus Diagnostic Chart 

P.54C-15

). 

Repair the CAN bus lines, and then go to Step 2.

STEP 2. Using diagnostic tool MB991958, read the 
combination meter diagnostic trouble code.

CAUTION

To prevent damage to diagnostic tool MB991958, always 
turn the ignition switch to the "LOCK" (OFF) position 
before connecting or disconnecting diagnostic tool 
MB991958.
Use diagnostic tool MB991958 to check whether combination 
meter DTC U1102 has been set.
(1) Connect diagnostic tool MB991958 to the data link 

connector.

(2) Turn the ignition switch to the "ON" position.
(3) Check whether combination meter DTC U1102 has been 

set.

Q: Is combination meter DTC U1102 set?

YES : Replace the hydraulic unit (integrated with 

ABS-ECU). 

NO :  Replace the combination meter.

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827

00DB076A

MB991910

DATA LINK

CONNECTOR

MB991824

MB991827