Mitsubishi Montero (2002-2004). Manual - part 1143

M-ASTC DIAGNOSIS

TSB Revision

MITSUBISHI ACTIVE SKID AND TRACTION CONTROL SYSTEM

35C-189

DIAGNOSIS

Required Special Tool:

• MB991223: Harness Set

STEP 1. Check the Active skid control system OFF 
indicator light circuit at M-ASTC-ECU connector E-121.
(1) Disconnect M-ASTC-ECU connector E-121 and measure at 

the harness side.

(2) Turn the ignition switch to the "ON" position.

(3) Measure the voltage between terminal 82 and ground. It 

should be approximately 12 volts (battery positive voltage).

Q: Is the voltage approximately 12 volts (battery positive 

voltage)?
YES : Replace the M-ASTC-ECU and then go to Step 6.
NO :  Go to Step 2.

AC203901

AC204627AR

CONNECTOR: E-121

E-121

E-121

HARNESS CONNECTOR: 
COMPONENT SIDE

AC205144AC

CONNECTOR: E-121

HARNESS CONNECTOR: 
COMPONENT SIDE

M-ASTC DIAGNOSIS

TSB Revision

MITSUBISHI ACTIVE SKID AND TRACTION CONTROL SYSTEM

35C-190

STEP2. Check combination meter connector D-03.
(1) Disconnect combination meter connector D-03 and 

measure at the combination meter side.

(2) Turn the ignition switch to the "ON" position.
(3) Measure the voltage between terminal 51 and ground. It 

should be approximately 12 volts (battery positive voltage).

Q: Is the voltage approximately 12 volts (battery positive 

voltage)?
YES : Go to Step 5.
NO :  Go to Step 3.

STEP 3. Check the harness wires between combination 
meter connector D-03 terminal 51 and terminal 62.
Q: Is the harness wire between combination meter 

connector D-03 terminal 51 and terminal 62 damaged?
YES : Go to Step 4.
NO :  Replace the combination meter (printed circuit board) 

and go to Step 6.

AC205146

CONNECTOR: D-03

COMBINATION METER
SIDE CONNECTOR

AD

AC205148

CONNECTOR: D-03

COMBINATION
METER SIDE
CONNECTOR

AB

M-ASTC DIAGNOSIS

TSB Revision

MITSUBISHI ACTIVE SKID AND TRACTION CONTROL SYSTEM

35C-191

STEP 4. Check the harness wires between ignition switch 
(IG1) connector D-204 terminal 2 and combination meter 
connector D-03 terminal 62.
NOTE: After inspecting combination meter connector D-03, 
ignition switch (IG1) connector D-204, junction block connector 
D-208 and D-210, inspect the wire. If combination meter con-
nector D-03, ignition switch (IG1) connector D-204, junction 
block connector D-208 and D-210 are damaged, repair or 
replace them. Refer to GROUP 00E, Harness Connector 
Inspection 

P.00-6

. Then go to Step 6.

Q: Is the harness wire between ignition switch (IG1) 

connector D-204 terminal 2 and combination meter 
connector D-03 terminal 62 damaged?
YES : Go to Step 6.
NO :  Replace the combination meter (printed circuit board) 

and go to Step 6.

AC204687AD

CONNECTOR: D-03

D-03 (GR)

HARNESS CONNECTOR: 
COMPONENT SIDE

AC204709

CONNECTOR: D-204

D-204

AD

2
5

6

3

4

1

HARNESS CONNECTOR:

COMPONENT SIDE

AC204624 AG

CONNECTORS: D-208, D-210

D-208

JUNCTION BLOCK
(FRONT VIEW)

JUNCTION BLOCK CONNECTOR

D-208

D-210

D-210

1 2 3

4

12

9

8

7

6

10

5

13

11

JUNCTION BLOCK CONNECTOR

M-ASTC DIAGNOSIS

TSB Revision

MITSUBISHI ACTIVE SKID AND TRACTION CONTROL SYSTEM

35C-192

STEP 5. Check the harness wires between combination 
meter connector D-03 terminal 51 and M-ASTC-ECU 
connector E-121 terminal 82.
NOTE: After inspecting combination meter connector combina-
tion meter connector D-03, intermediate connector E-122 and 
M-ASTC-ECU connector E-121, inspect the wire. If combina-
tion meter connector D-03, intermediate connector E-122 and 
M-ASTC-ECU connector E-121 are damaged, repair or replace 
them. Refer to GROUP 00E, Harness Connector Inspection 

P.00-6

. Then go to Step 6.

Q: Is the harness wire between combination meter 

connector D-03 terminal 51 and M-ASTC-ECU connector 
E-121 terminal 82 damaged?
NO :  Go to Step 6.
YES : Repair it and then go to Step 6.

AC204687AD

CONNECTOR: D-03

D-03 (GR)

HARNESS CONNECTOR: 
COMPONENT SIDE

AC203901

AC204627AR

CONNECTOR: E-121

E-121

E-121

HARNESS CONNECTOR: 
COMPONENT SIDE

AC204548

E-122(L)

AP

CONNECTOR: E-122

2

1

3

13

12

14

21

10

5

4

6

16

15

17

7 8 9

19

18

20

11

22