Code No.B1400: Driver’s Air Bag Module (1st Squib) System Fault 1 (Short Circuit between Terminals
of the Squib Circuit)
Code No.B1480: Driver’s Air Bag Module (2nd Squib) System Fault 1 (Short Circuit between Terminals
of the 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 : Gray R : Red P : Pink V : Violet

AIR BAG MODULE
(SQUIB)
(DRIVER'S SIDE)

CLOCK
SPRING

SRS-ECU

: CONNECTOR LOCK SWITCH
CONNECTOR CONNECTED: ON
CONNECTOR DISCONNECTED: OFF

NOTE

CONNECTOR
LOCK SWITCH

Driver's Air Bag Module (1st and 2nd Squib) Circuit

TROUBLESHOOTING

SUPPLEMENTAL RESTRAINT SYSTEM (SRS)

52B-19

CAUTION

If diagnosis code B1400 <1st squib> or B1480
<2nd squib> is set in the SRS-ECU, always
diagnose the CAN bus lines.

OPERATION

• The SRS-ECU judges how severe a collision is

by detecting signals from the front impact sensors
and the front air bag analog G-sensor. If the
impact is over a predetermined level, the
SRS-ECU sends an ignition signal. At this time, if
the front air bag safing G-sensor is on, the SRS
air bag will inflate.

• The ignition signal is input to the air bag module

via the clock spring to inflate the air bag.

DIAGNOSIS CODE SET CONDITIONS

• This diagnosis code is set if there is abnormal

resistance between the input terminals of the
driver's side air bag module (squib). The most
likely causes for this code to be set are the
followings:

• Short circuit in driver’s air bag module (squib)

or harness

• Short circuit in the clock spring

However, if no diagnosis code reset, the SRS
warning lamp will be turned off (diagnosis code will
OK).

PROBABLE CAUSES

• Improper engaged connector or defective short

spring*

• Short circuit in the clock spring

• Short circuit between the driver's air bag module

(squib) circuit terminals

• Damaged connector(s)

• Malfunction of the SRS-ECU

NOTE: *: The squib circuit connectors integrate a
"short" spring (which prevents the air bag from
deploying unintentionally due to static electricity by
shorting the positive wire to the earth wire in the
squib circuit when the connectors are disconnected).
(Refer to

P.52B-5

). Therefore, if connector C-119,

C-309 or C-303 is damaged or improperly engaged,
the short spring may not be released when the
connector is connected.

DIAGNOSIS PROCEDURE

STEP 1. MUT-III CAN bus diagnostics

Use the MUT-III to diagnose the CAN bus lines.

Q: Is the check result normal?

YES :

Go to Step 2.

NO :

Repair the CAN bus line (Refer to GROUP
54D, Diagnosis

P.54D-16

STEP 2. Check whether the diagnosis code is
reset.

Check again if the diagnosis code is set.
(1) Erase the diagnosis code.
(2) Ignition: LOCK (OFF) position to ON
(3) On completion, check that the diagnosis code is

not reset.

Q: Is the diagnosis code set?

YES :

Go to Step 3.

NO :

There is an intermittent malfunction such as
poor engaged connector(s) or open circuit
(Refer to GROUP 00, How to Cope with
Intermittent Malfunction

P.00-5

STEP 3. MUT-III diagnosis code

CAUTION

To prevent damage to MUT-III, always turn the
ignition switch to the "LOCK" (OFF) position
before connecting or disconnecting MUT-III.
(1) Turn the ignition switch to the "ON" position.
(2) Check if the diagnosis code is set.
(3) Turn the ignition switch to the "LOOK" (OFF)

position.

Q: Is diagnosis code B1519 set?

YES :

Go to Step 4.

NO :

Go to Step 5.

STEP 4. Connector check: SRS-ECU connector
C-119.

Q: Is the connector correctly engaged?

YES :

Go to Step 5.

NO :

Engage the connector correctly. Then go to
Step 10.

AC311438 AD

C-119 (Y)

Connector: C-119

Harness side
(front view)

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