Code
No.B1411: Passenger’s (front) air bag module (squib) system (open-circuited in the
squib circuit)
OPERATION
Only when the frontal impact exceeding the threshold is simultaneously detected (turned
ON) by the front impact sensor as well as by the analog G-sensor and safing G-sensor in SRS-ECU,
the electric current is supplied from SRS-ECU to the passenger’s (front) air bag module
(squib).
TROUBLE JUDGEMENT
The code is set when the open circuit occurs to the SRS-ECU passenger’s (front)
air bag module (squib) circuit. PROBABLE CAUSES
Open circuit in the passenger’s (front) air bag module (squib) circuit
Improper connector contact
Malfunction of the SRS-ECU
DIAGNOSIS PROCEDURE
STEP 1. Diagnosis check by dummy resistor connection.
(1)Check that the negative auxiliary battery terminal is disconnected. If the negative
auxiliary battery terminal is connected, disconnect it.
(2)Release the claw (1) of the lock lever of B-107 passenger’s (front) air bag module
connector, and lift the lock lever to the direction of the arrow (2), then remove the connector.
(3)Connect special tool dummy resistor (MB991865) to special tool resistor harness (MB991866). (4)
caution
Do not insert a test probe into the terminal from
its front side directly as the connector contact pressure may be weakened.
Insert special tool (MB991866) into the harness side connector B-107 by backprobing. (5)Connect the negative auxiliary battery terminal. (6)After erasing the diagnosis code memory, check the diagnosis code again. (7)Disconnect the negative auxiliary battery terminal.
Q.
Is diagnosis code B1411 set?
Go to Step 2
Replace the passenger’s (front) air bag module (Refer to ).
STEP 2. Resistance measurement between the B-112 SRS-ECU connector
and the B-107 passenger’s (front) air bag module connector.
(1)Check that the negative auxiliary battery terminal is disconnected. If the negative
auxiliary battery terminal is connected, disconnect it.
(2)Disconnect the B-112 SRS-ECU connector.
(3)
danger
To release the connector short spring in the following operations, disconnect this harness
side connector, and keep the squib circuit shorted.
Release the claw (1) of the lock lever of B-107 passenger’s (front) air bag module
connector, and lift the lock lever to the direction of the arrow (2), then remove the connector.
(4)
caution
The short spring may not be released due to the insufficient insertion. Therefore, insert
the insulator for 4 mm or more.
Insert the insulator (width: 3 mm, thickness: 0.5 mm) such as cable tie between the terminals
Nos. 21 and 22, and then release the short spring. (5)
caution
Do not insert a test probe into the
terminal from its front side directly as the connector contact pressure may be weakened.
Take the measurements below at the B-112 and B-107 harness side connectors.
Continuity between the B-112 SRS-ECU connector terminal
No. 21 and the B-107 passenger’s (front) air bag module connector terminal No. 1
Continuity between the B-112 SRS-ECU connector terminal No. 22 and the B-107 passenger’s
(front) air bag module connector terminal No. 2
OK: Continuity (Less than 2 Ω)
Q.
Is the check results normal?
Go to Step 3
Repair the harness wires between the B-112 SRS-ECU connector (terminal No.21 and
22) and B-107 passenger’s (front) air bag module connector (terminal No.1 and 2).
STEP 3. Check whether the diagnosis code is reset.
Q.
Is diagnosis code B1411 set?
Replace the SRS-ECU (Refer to ).
An intermittent malfunction is suspected (Refer to GROUP 00, How to Cope with
Intermittent Malfunction ).
)
)
)
)
)
Go to Step 2
Replace the passenger’s (front) air bag module (Refer to 
).)
