Mitsubishi Montero (2004+). Manual - part 1003

BASIC BRAKE SYSTEM DIAGNOSIS

TSB Revision

BASIC BRAKE SYSTEM

35A-11

STEP 6. Retest the system.

Q: Is the symptom eliminated?

YES : 

The procedure is complete.

NO : 

Start over at Step 1. If a new symptom 
appears, refer to the appropriate symptom 
chart (

P.35A-6

).

INSPECTION PROCEDURE 8: Groaning, Clicking or Rattling Noise when Brakes are not Applied.

DIAGNOSIS

STEP 1. Check for looseness of the wheel nuts.

Q: Are the wheel nuts loose?

YES : 

Tighten to 108 

± 10 N⋅m (80 ± 7 ft-lb). Then 

go to Step 4.

NO : 

Go to Step 2.

STEP 2. Check for looseness of the caliper 
installation bolt.

Q: Is the caliper installation bolt loose?

YES : 

Tighten to 113 

± 9 N⋅m (83 ± 7 ft-lb) for the 

front caliper, or 100 

± 10 N⋅m (74 ± 7 ft-lb) 

for the rear caliper. Then go to Step 4.

NO : 

Go to Step 3.

STEP 3. Check the wheel bearings for wear, 
damage or dryness.

For front wheel, refer to GROUP 26, Hub and 
Knuckle Assembly 

P.26-18

. For rear wheel, refer to 

GROUP 27, Rear Hub Assembly 

P.27-13

.

Q: Is there fault?

YES : 

Apply grease or replace the wheel bearings. 

Then go to Step 4.

NO : 

Go to Step 4.

STEP 4. Retest the system.

Q: Is the symptom eliminated?

YES : 

The procedure is complete.

NO : 

Start over at Step 1. If a new symptom 
appears, refer to the appropriate symptom 
chart (

P.35A-6

).

HYDRAULIC BRAKE BOOSTER (HBB) DIAGNOSIS

TSB Revision

BASIC BRAKE SYSTEM

35A-12

HYDRAULIC BRAKE BOOSTER (HBB) DIAGNOSIS

INTRODUCTION

M1351012800059

The hydraulic brake booster (HBB) accumulates the 
high-pressure brake fluid in the accumulator by oper-
ating the pump motor. Even though the working 
sound of the pump motor can be heard during opera-
tion, this sound is usually generated at normal opera-
tion of the HBB and is not an indication of a 
malfunction.

HBB Diagnostic Trouble Code Detection 
Conditions

HBB diagnostic trouble codes (HBB DTCs) are set 
under different conditions, depending on the mal-
function detected. Most HBB DTCs will only be set 
during vehicle operation. Some HBB DTCs will also 
be set during the HBB self-check immediately after 
the engine is started.

After erasing an HBB DTC, duplicate the HBB DTC 
set conditions to see if it resets. Depending on the 
detection timing and set conditions for the specific 
HBB DTC, you must either drive the vehicle or turn 
the engine off and restart it. To set the proper condi-
tions for that DTC again, refer to "HBB DTC SET 
CONDITIONS" for each HBB DTC that you are trying 
to reset.

DIAGNOSTIC TROUBLESHOOTING STRATEGY

M1351012900056

Use these steps to plan your diagnostic strategy. If 
you follow them carefully, you will be sure that you 
have exhausted most of the possible ways to find an 
HBB fault.
1. Gather information about the problem from the 

customer.

2. Verify that the condition described by the 

customer exists.

3. Check the vehicle for any HBB DTC.
4. If you cannot verify the condition and no HBB 

DTC sets, it can be assumed that the malfunction 
is intermittent. Refer to GROUP 00, How to use 
Troubleshooting/Inspection Service Points 

− How 

to Cope with Intermittent Malfunctions 

P.00-6

.

5. If you can verify the condition but no HBB DTC 

sets, or the system cannot communicate with the 
scan tool, check that the basic brake system is 
operating properly.

• If the basic brake system is not operating prop-

erly, refer to "Basic Brake System Diagnosis" 
(

P.35A-6

).

• If the basic brake system is operating properly, 

refer to "Symptom Chart" (

P.35A-82

).

6. If an HBB DTC sets, record the number of the 

DTC, then erase the DTC from the memory using 
the scan tool.

7. Duplicate the HBB DTC set conditions to see if 

the same HBB DTC will set again.

• If the same HBB DTC sets again, perform the 

diagnostic procedures for the DTC. Refer to 

P.35A-17

.

• If you cannot make the same HBB DTC set 

again, it can be assumed that the malfunction is 
intermittent. Refer to GROUP 00, How to use 
Troubleshooting/Inspection Service Points 

− How 

to Cope with Intermittent Malfunctions 

P.00-6

.

HYDRAULIC BRAKE BOOSTER (HBB) DIAGNOSIS

TSB Revision

BASIC BRAKE SYSTEM

35A-13

BRAKE WARNING LIGHT CHECK

M1351013000056

Check that the brake warning light illuminates as follows:
1. Check that the brake fluid level in the reservoir is between 

the "MIN" and the "MAX" lines.

2. Choke the wheels and release the parking brake.
3. When the ignition switch is turned to the "ON" position, the 

brake warning light illuminates.

4. When the ignition switch is turned from the "START" position 

back to the "ON" position, the brake warning light illuminates 
for approximately 3 seconds and then switches off.

5. If the illumination is other than the above, check the 

diagnostic trouble codes.

TROUBLE CODE DIAGNOSIS

M1351011200098

Retrieving HBB Diagnostic Trouble Codes

Required Special Tools:

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

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

• MB991827: MUT-III USB Cable

• MB991911: MUT-III Main Harness B

AC000682 AB

BRAKE
WARNING
LIGHT

IGNITION
SWITCH

ILLUMINATED

NOT
ILLUMINATED

APPROXIMATELY 3S

LOCK, ACC

ON

START

BRAKE WARNING LIGHT

HYDRAULIC BRAKE BOOSTER (HBB) DIAGNOSIS

TSB Revision

BASIC BRAKE SYSTEM

35A-14

CAUTION

To prevent damage to scan tool MB991958, always turn the 
ignition switch to the "LOCK" (OFF) position before con-
necting or disconnecting scan tool MB991958.
1. Ensure that the ignition switch is at the "LOCK" (OFF) 

position.

2. Start up the personal computer.
3. Connect special tool MB991827 to special tool MB991824 

and the personal computer.

4. Connect special tool MB991911 to special tool MB991824.
5. Connect special tool MB991911 to the data link connector.
6. Turn the power switch of special tool MB991824 to the "ON" 

position.
NOTE: When special tool MB991824 is energized, special 
tool MB991824 indicator light will be illuminated in a green 
color.

7. Start the MUT-III system on the personal computer.
NOTE: Disconnecting scan tool MB991958 is the reverse of the 
connecting sequence, making sure that the ignition switch is at 
the "LOCK" (OFF) position.

Erasing HBB Diagnostic Trouble Codes

NOTE:  If the M-ASTC-ECU functions have stopped due to the 
fail-safe function, the HBB diagnostic trouble code cannot be 
erased.

Required Special Tools:

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

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

• MB991827: MUT-III USB Cable

• MB991911: MUT-III Main Harness B

CAUTION

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

NOTE: If the battery voltage is low, diagnostic trouble codes 
will not be set. Check the battery if scan tool MB991958 
does not display.

AC307591 AC

MB991911

MB991824

MB991827

AC307591

DATA LINK

CONNECTOR