Mitsubishi Montero (2004+). Manual - part 1012

HYDRAULIC BRAKE BOOSTER (HBB) DIAGNOSIS

TSB Revision

BASIC BRAKE SYSTEM

35A-47

STEP 14. Check the following harness wires.

• The wire between HBB connector B-18 (terminal 31) and 

motor relay A connector B-53X (terminal 4)

AC204626 AB

CONNECTOR: B-18

B-18 (B)

HARNESS CONNECTOR : 
COMPONENT SIDE

34

32

31

33

35

B-18

AC204551

3  2  1

5     4

1  2  3

4     5

RELAY BOX CONNECTOR

AC

CONNECTOR: B-53X

B-53X

HYDRAULIC BRAKE BOOSTER (HBB) DIAGNOSIS

TSB Revision

BASIC BRAKE SYSTEM

35A-48

• The wire between HBB connector B-17 (terminal 2) and 

motor relay B connector B-54X (terminal 5)

Q: Is any harness wire damaged?

YES : Repair or replace the faulty harness wire and then go 

to Step 25.

NO :  Go to Step 15.

AC204629 AE

CONNECTOR: B-17

B-17 (GR)

HARNESS CONNECTOR: 
COMPONENT SIDE

1

2

3

4

5

6

7

8

B-17

AC204551

3  2  1

5     4

1  2  3

4     5

RELAY BOX CONNECTOR

AD

CONNECTOR: B-54X

B-54X

HYDRAULIC BRAKE BOOSTER (HBB) DIAGNOSIS

TSB Revision

BASIC BRAKE SYSTEM

35A-49

STEP 15. Check the following connectors.

• M-ASTC-ECU connectors E-119 and E-120

Check connectors, for loose, corroded or damaged terminals, 
or terminals pushed back in the connector.
Q: Are the connectors and terminals in good condition?

YES : Go to Step 16.
NO :  Repair the faulty connector or terminal. Then go to 

Step 25.

AC203901

AC204627 AD

CONNECTORS: E-119, E-120

E-119

M-ASTC-ECU CONNECTORS

E-119

E-120

E-120

HYDRAULIC BRAKE BOOSTER (HBB) DIAGNOSIS

TSB Revision

BASIC BRAKE SYSTEM

35A-50

STEP 16. Check the ignition switch (IG2) circuit at 
M-ASTC-ECU harness connector E-120.

(1) Disconnect M-ASTC-ECU connector E-120.
(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal 48 and ground. The 

voltage should measure approximately 12 volts (battery 
positive voltage).

Q: Is battery positive voltage (approximately 12 volts) 

present?
YES : Go to Step 17.
NO :  Go to Step 18.

AC203901

AC204627AE

CONNECTOR: E-120

M-ASTC-ECU CONNECTOR

E-120

E-120

AC204729 AB

HARNESS CONNECTOR: 
COMPONENT SIDE

E-120