Mitsubishi L200. Manual — part 615

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-131

DIAGNOSIS PROCEDURE

STEP 1. Check the diagnosis code by connecting
a dummy resistor. (M.U.T.-III diagnosis code)
(1) Disconnect the negative battery terminal.

AC903877AF

Connector: D-36 <LHD>

D-36 (Y)

Harness side
connector
(rear view)

<CLUB CAB>

AC903879AD

Connector: D-36 <RHD>

D-36 (Y)

Harness side
connector
(rear view)

<CLUB CAB>

AC903885AM

Connector: D-36 <LHD>

D-36 (Y)

Harness side
connector
(rear view)

<DOUBLE CAB>

AC903886 AH

Connector: D-36 <RHD>

D-36 (Y)

Harness side
connector
(rear view)

<DOUBLE CAB>

(2) Disconnect side-airbag module (RH) connector

D-36. When disconnecting connector D-36,
unlock the connector by sliding the locking button
to the direction of the arrow as shown in the
figure, and then disconnect the connector.

AC507310 BG

D-36

Side-airbag

module (RH) connector

D-36
Harness side
connector

MB991865
(Dummy resistor: 3 )

MB991866

(Resistor harness)

(3) Connect special tool dummy resistor (MB991865)

to special tool resistor harness (MB991866).

CAUTION

Do not insert a test probe into the terminal from
its front side directly as the connector contact
pressure may be weakened.
(4) Insert special tool (MB991866) into the harness

side connector D-36 by backprobing.

(5) Connect the negative battery terminal.
(6) Erase the diagnosis code memory, and check the

diagnosis code.

Q: Is diagnosis code B1421 set?

YES :

Go to Step 2

NO :

Replace the front seatback assembly (RH)
(Refer to

P.52B-276

).

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-132

STEP 2. Resistance measurement between SRS-
ECU connector C-155 (terminal No.53 and 54)
and the side-airbag module (RH) connector D-36
(terminal No.2 and 1).
(1) Disconnect the negative battery terminal.

AC801404

AK

Connector: C-155

C-155 (Y)

Harness side
connector
(rear view)

(2) Disconnect SRS-ECU connector C-155.

DANGER

To prevents the air bag from deploying unin-
tentionally, disconnect the side-airbag mod-
ule (RH) connector D-36 to short the squib
circuit.

AC903877AF

Connector: D-36 <LHD>

D-36 (Y)

Harness side
connector
(rear view)

<CLUB CAB>

AC903879AD

Connector: D-36 <RHD>

D-36 (Y)

Harness side
connector
(rear view)

<CLUB CAB>

AC903885AM

Connector: D-36 <LHD>

D-36 (Y)

Harness side
connector
(rear view)

<DOUBLE CAB>

AC903886 AH

Connector: D-36 <RHD>

D-36 (Y)

Harness side
connector
(rear view)

<DOUBLE CAB>

AC706606

AF

Locking button

(3) Disconnect side-airbag module (RH) connector

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-133

D-36. When disconnecting connector D-36,
unlock the connector by sliding the locking button
to the direction of the arrow as shown in the
figure, and then disconnect the connector.

AC801564

Section
A - A

C-155 Harness side connectors
(front view)

Cable tie

Terminal

7 mm or more

AE

Short spring

A

A

CAUTION

Insert an insulator such as a cable tie to a depth
of 7 mm or more, otherwise the short spring will
not be released.
(4) Insert a cable tie [3 mm wide, 0.5 mm thick]

between terminals 53, 54 and the short spring to
release the short spring.

AC800962 BM

C-155
Harness side
connector
(rear view)

D-36
Harness side
connector
(rear view)

CAUTION

Do not insert a test probe into the terminal from
its front side directly as the connector contact
pressure may be weakened.
(5) Resistance measurement between the following

terminals.

• SRS-ECU connector C-155 terminal No.53

and the side-airbag module (RH) connector
D-36 terminal No.2

• SRS-ECU connector C-155 terminal No.54

and the side-airbag module (RH) connector
D-36 terminal No.1

OK: Continuity (Less than 2

Ω)

Q: Are the check results normal?

YES :

Go to Step 3

NO :

Repair the harness wires between SRS-
ECU connector C-155 (terminal No.53 and
54) and side-airbag module (RH) connector
D-36 (terminal No.2 and1).

STEP 3. Check whether the diagnosis code is
reset.

Q: Is diagnosis code B1421 set?

YES :

Replace the SRS-ECU (Refer to

P.52B-

266

).

NO :

An intermittent malfunction is suspected
(Refer to GROUP 00, How to Cope with
Intermittent Malfunction ).

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-134

Code No.B1422: Side-airbag module (RH) (squib) system (short-circuited to the earth)

AC805811

NOTE

: CONNECTOR LOCK SWITCH

CONNECTOR COUPLED: ON
CONNECTOR UNCOUPLED: OFF

Side-Airbag Module (RH) (Squib) Circuit

Wire colour code
B : Black LG : Light green G : Green L : Blue W : White Y : Yellow SB : Sky blue
BR : Brown O : Orange GR : Grey R : Red P : Pink V : Violet PU : Purple SI : Silver

AB

SRS-ECU

SIDE-AIRBAG
MODULE (SQUIB) (RH)

OPERATION

• The SRS-ECU judges how severe a collision is

by detecting signals from the left and right side
impact sensors. If the impact is over a predeter-
mined level, the SRS-ECU sends an ignition sig-
nal. At this time, if the side air bag safing G-
sensor is on, the SRS side-airbag will inflate.

• The ignition signal is input to the side-airbag

module to inflate the side-airbag.

DIAGNOSIS CODE SET CONDITIONS
This diagnosis code is set if the side-airbag module
(RH) squib wire(s) are short-circuited to the earth.

PROBABLE CAUSES

• Damaged harness wires and connectors

• Short to the earth in the side-airbag module (RH)

(squib) harness

• Malfunction of the SRS-ECU