Mitsubishi Montero (2004+). Manual - part 1117

M-ASTC DIAGNOSIS

TSB Revision

MITSUBISHI ACTIVE SKID AND TRACTION CONTROL SYSTEM

35C-179

STEP 1. Check steering wheel sensor connector D-225 and 
joint connector (9) D-131.

CAUTION

If there is a problem in the connector(s) (including termi-
nals) or wire(s) of the instrument panel wiring harness 
assembly (the wiring harness connected to the steering 
wheel sensor, the data link connector and the resistor) and 
the transmission wiring harness assembly (the wiring har-
ness connected to the G and yaw rate sensor connector 
and intermediate connector E-123), cut and repair the 
defective wire so that the frayed end of the twisted wire 
should be within 10 cm (4.0 inches). If it exceeds 10 cm (4.0 
inches), twist the wiring harness just like the original 
twisted wire. If the frayed end exceeds 10 cm (4.0 inches), 
a communication error may be caused.
Q: Is steering wheel sensor connector D-225 and joint 

connector (9) D-131 in good condition?
YES : Go to Step 2.
NO :  Repair or replace the connector.

AC204170

CONNECTOR: D-131

AT

6

1

9 8

2

7

10

12 11

4

5

3

AC204172

CONNECTOR: D-225

HARNESS SIDE

AD

3 2

1

4

5

AC203824

CONNECTOR

TWISTED WIRE

AB

10 cm
 (4.0 inches)

M-ASTC DIAGNOSIS

TSB Revision

MITSUBISHI ACTIVE SKID AND TRACTION CONTROL SYSTEM

35C-180

STEP 2. Check the CAN bus line for open circuit. Measure 
at joint connector (9) D-131 and steering wheel sensor 
connector D-225.

CAUTION

Before checking CAN bus lines and their interconnected 
components, "ground" yourself, by touching a metal 
object such as an unpainted pipe, this will discharge any 
potentially damaging static that may have built up.

CAUTION

When measuring resistance value or voltage in CAN bus 
lines, use a digital multimeter. If not using a digital multim-
eter, the equipments connected through the CAN bus lines 
may be damaged.
(1) Disconnect joint connector (9) D-131 and steering wheel 

sensor connector D-225, and measure the resistance 
between joint connector (9) and the steering wheel sensor 
connector.

(2) Turn the ignition switch to the LOCK (OFF) position.

CAUTION

Disconnect the negative battery terminal when measuring 
the resistance value in the CAN bus line. If you fail to do 
so, the equipments connected through the CAN bus lines 
may be damaged.
(3) Disconnect the negative battery terminal.

AC204170

CONNECTOR: D-131

AT

6

1

9 8

2

7

10

12 11

4

5

3

AC204172

CONNECTOR: D-225

HARNESS SIDE

AD

3 2

1

4

5

M-ASTC DIAGNOSIS

TSB Revision

MITSUBISHI ACTIVE SKID AND TRACTION CONTROL SYSTEM

35C-181

CAUTION

Always use the test harness when measuring the voltage 
or resistance value at the female connector. If you fail to do 
so, connectors may be damaged.
(4) Measure the resistance values between joint connector (9) 

D-131 terminal 2 and steering wheel sensor connector 

D-225 terminal 3, and between joint connector (9) D-131 
terminal 5 and steering wheel sensor connector D-225 
terminal 4.

• The resistance should measure 2 ohms or less.

CAUTION

If you repair the CAN bus line of the instrument panel wir-
ing harness assembly (the wiring harness connected to 
the steering wheel sensor, the data link connector and the 
resistor) and the transmission wiring harness assembly 
(the wiring harness connected to the G and yaw rate sen-
sor connector and intermediate connector E-123), observe 
the precautions regarding how to repair wiring harness. If 
a new wire is added or a splice point is modified for the 
CAN_L or CAN_H line, an error in the CAN communication 
may be caused.
Q: Does the resistance measure 2 ohms or less?

YES : Diagnose the steering wheel sensor. Refer to 

P.35C-33

.

NO :  Repair the wiring harness wires between joint 

connector (9) and the steering wheel sensor 
connector.

AC204582

HARNESS SIDE: D-225

AP

HARNESS SIDE: D-131

6

1

9 8

2

7

10

12 11

4

5

3

TEST 
HARNESS

3 2

1

4

5

TEST 
HARNESS

AC204582

HARNESS SIDE: D-225

AQ

HARNESS SIDE: D-131

6

1

9 8

2

7

10

12 11

4

5

3

TEST 
HARNESS

3 2

1

4

5

TEST 
HARNESS

M-ASTC DIAGNOSIS

TSB Revision

MITSUBISHI ACTIVE SKID AND TRACTION CONTROL SYSTEM

35C-182

Diagnostic Item 7: CAN bus line diagnostics (between the main bus line and the G and yaw rate 
sensor)

CAUTION

Prior to this diagnosis procedure, diagnose the 
CAN main bus line.

CAUTION

Before checking CAN bus lines and their inter-
connected components, "ground" yourself, by 
touching a metal object such as an unpainted 
pipe, this will discharge any potentially damag-
ing static that may have built up.

CAUTION

When measuring resistance value or voltage in 
CAN bus lines, use a digital multimeter. If not 
using a digital multimeter, the equipments con-
nected through the CAN bus lines may be dam-
aged.

CAUTION

Disconnect the negative battery terminal when 
measuring the resistance value in the CAN bus 
line. If you fail to do so, the equipments con-
nected through the CAN bus lines may be dam-
aged.

CAUTION

Always use the test harness when measuring the 
voltage or resistance value at the female connec-
tor. If you fail to do so, connectors may be dam-
aged.

CAUTION

If there is a problem in the connector(s) (includ-
ing terminals) or wire(s) of the instrument panel 
wiring harness assembly (the wiring harness 
connected to the steering wheel sensor, the data 
link connector and the resistor) and the trans-
mission wiring harness assembly (the wiring har-
ness connected to the G and yaw rate sensor 
connector and intermediate connector E-123), 
cut and repair the defective wire so that the 
frayed end of the twisted wire should be within 
10 cm (4.0 inches). If it exceeds 10 cm (4.0 

inches), twist the wiring harness just like the 
original twisted wire. If the frayed end exceeds 10 
cm (4.0 inches), a communication error may be 
caused.

CAUTION

If you repair the CAN bus line of the instrument 
panel wiring harness assembly (the wiring har-
ness connected to the steering wheel sensor, the 
data link connector and the resistor) and the 
transmission wiring harness assembly (the wir-
ing harness connected to the G and yaw rate 
sensor connector and intermediate connector 
E-123), observe the precautions regarding how to 
repair wiring harness. If a new wire is added or a 
splice point is modified for the CAN_L or CAN_H 
line, an error in the CAN communication may be 
caused.

CAUTION

If there is a problem in the CAN bus line or the 
connectors on the control wiring harness assem-
bly (the wiring harness connected to the 
M-ASTC-ECU, the power control module and 
intermediate connector E-123), do not attempt to 
repair the wiring harness or connector(s), but 
replace the wiring harness assembly. If a wire is 
added or the connector(s) are repaired, an error 
in the CAN communication may be caused.

AC203824

CONNECTOR

TWISTED WIRE

AB

10 cm
 (4.0 inches)