Code No.B1410: Passenger’s (front) air bag module (squib) system (short-circuited between terminals of the squib circuit)

OPERATION

TROUBLE JUDGEMENT

PROBABLE CAUSES

Improper engaged connector or defective short spring*
Short circuit between the passenger’s (front) 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 bags from being unintentionally deployed because of static electricity by shorting the positive wire to the earth wire in the squib circuit when the connectors are disconnected). Therefore, when the above codes are set, the short spring may not be released due to the damaged connector even when the connectors are connected.

DIAGNOSIS PROCEDURE

STEP 1. M.U.T.-III diagnosis code.

Q. Is diagnosis code B1519 set?

	Go to Step 2

	Go to Step 3

STEP 2. Connector lock check: The B-112 SRS-ECU connector.

(1)Check that the negative auxiliary battery terminal is disconnected. If the negative auxiliary battery terminal is connected, disconnect it.

(2)After disconnecting the B-112 SRS-ECU connector, connect it again.

(3)Connect the negative auxiliary battery terminal.

(4)After erasing the diagnosis code memory, check the diagnosis code again.

(5)Disconnect the negative auxiliary battery terminal.

Q. Is diagnosis code B1410 set?

	Go to Step 3

	The procedure is complete. It is assumed that diagnosis code B1410 set as connector B-112 was engaged improperly.

STEP 3. Connector lock check: The B-112 SRS-ECU connector and 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)After disconnecting B-107 passenger’s (front) air bag module connector and B-112 SRS-ECU connector, connect the connector again. 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 the negative auxiliary battery terminal.
(4)After erasing the diagnosis code memory, check the diagnosis code again.
(5)Disconnect the negative auxiliary battery terminal.

Q. Is diagnosis code B1410 set?

Go to Step 4

The procedure is complete. It is assumed that diagnosis code B1410 set as connector B-107 or B-112 was engaged improperly.

STEP 4. 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)Check that the passenger’s air bag cut off switch is "ON" position.
(6)Connect the negative auxiliary battery terminal.
(7)After erasing the diagnosis code memory, check the diagnosis code again.
(8)Disconnect the negative auxiliary battery terminal.

Q. Is diagnosis code B1410 set?

Go to Step 5

Replace the passenger’s (front) air bag module (Refer to

STEP 5. Resistance measurement at the B-112 SRS-ECU 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)Check that the passenger’s air bag cut off switch is "ON" position.
(6)

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 harness side connector.

Continuity between No. 21 and No. 22

OK: No continuity

Q. Is the check result normal?

Go to Step 6

Repair the harness wires between 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 6. Check whether the diagnosis code is reset.

Q. Is diagnosis code B1410 set?

	Replace the SRS-ECU (Refer to ).

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