Mitsubishi Grandis. Manual - part 1031

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-176

STEP 8. Check the harness for short circuit 
between passenger’s air bag off indicator lamp 
C-25 (terminal No.3) and SRS-ECU connector 
C-119 (terminal No.21).

Q: Are the harness wires between SRS-ECU 

connector C-119 (terminal No.21) and the 
passenger’s air bag off indicator lamp C-25 
(terminal No.3) in good condition?

YES : 

Go to Step 9 .

NO : 

Repair the harness wires. Then go to Step 
10 .

STEP 9. Check the passenger’s air bag off 
indicator lamp.
(1) Disconnect the negative battery terminal.

(2) Disconnected the SRS-ECU connector C-26, and 

measure at the wiring harness side.

(3) Connect the negative battery terminal.
(4) Turn the ignition switch to the "ON" position.

CAUTION

Do not insert a test probe into the terminal from 
its front side directly, as the connector contact 
pressure may be weakened.
(5) Connect terminal No.21 to earth.

Q: Does the indicator lamp illuminate?

YES : 

Erase the diagnosis code memory, and 

check the diagnosis code. If diagnosis code 
B1489 set, replace the SRS-ECU. (Refer to 

P.52B-223

). Go to Step 10  .

NO : 

Replace the passenger’s air bag off 
indicator lamp (Refer to GROUP 52A, 
Instrument Panel Assembly 

P.52A-2

). Go to 

Step 10 . 

STEP 10. Check whether the diagnosis code is 
reset.

Q: Is diagnosis code B1489 set?

AC310613

BI

Connector: C-25 <LHD>

Harness side

AC310631BE

Connector: C-25 <RHD>

Harness side

AC311438 AD

C-119 (Y)

Connector: C-119

Harness side
(front view)

AC311438 AD

C-119 (Y)

Connector: C-119

Harness side
(front view)

AC308206

42

31

38

27

21

41

28

39

22

30

25

47

36

33

44

34

45

37

48

26

29

23

40

32

43

35

46

24

B

A

C-119 Harness side
connector (rear view)

AD

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-177

YES : 

Return to Step 1 .

NO : 

The procedure is complete (If no 
malfunctions are found in all steps, an 
intermittent malfunction is suspected). Refer 
to GROUP 00, How to Use 
Troubleshooting/Inspection Service Points 

P.00-5

. 

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-178

Code No.B1489: Passenger’s Air Bag Off Indicator Lamp Drive Circuit System Fault 1 (Light does not 
Switch Off).

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

SRS-ECU

IGNITION
SWITCH (IG1)

PASSENGER'S
AIR BAG OFF
INDICATOR LAMP

RELAY
BOX

TAIL LAMP
RELAY

FRONT-ECU

Air Bag Off Indicator Lamp Drive Circuit <LH drive vehicles>

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-179

CAUTION

If diagnosis code B1489 is set in the SRS-ECU, 
always diagnose the CAN main bus line.

OPERATION

• Power for the passenger’s air bag off indicator 

lamp is supplied from the ignition switch (IG1).

• The passenger’s air bag off indicator lamp 

illuminates when the ignition switch is turned to 
the "ON" position and goes out after 
approximately 7 seconds if there is not a 
malfunction in the SRS system.

• If a failure occurs in the system, the SRS-ECU 

will stop sending that SRS warning lamp "OFF" 
signal, thus causing the combination meter to 
illuminate the SRS warning lamp.

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

SRS-ECU

IGNITION
SWITCH (IG1)

PASSENGER'S
AIR BAG OFF
INDICATOR LAMP

RELAY
BOX

TAIL LAMP
RELAY

FRONT-ECU

Air Bag Off Indicator Lamp Drive Circuit <RH drive vehicles>