Toyota Corolla Cross: Second Row Left Seat Belt Pretensioner Deployment Control Circuit Resistance Below Threshold (B00731A)

DESCRIPTION

DTC No.	Detection Item	DTC Detection Condition	Trouble Area	Warning Indicate	Test Mode / Check Mode
B00731A	Second Row Left Seat Belt Pretensioner Deployment Control Circuit Resistance Below Threshold	The airbag ECU assembly detects a line short in the rear pretensioner squib LH circuit for 2 seconds during the primary check. Rear seat outer belt assembly LH malfunction Airbag ECU assembly malfunction	Harness or connector Rear seat outer belt assembly LH Airbag ECU assembly	Comes on	Applies to check mode

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

• After the ignition switch is turned off, there may be a waiting time before disconnecting the negative (-) battery terminal.

  Click here

  HINT:

  When disconnecting and reconnecting the battery, there is an automatic learning function that completes learning when the respective system is used.

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• After replacing the airbag ECU assembly, refer to work procedure.

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HINT:

• To perform the simulation method, enter check mode (signal check) with the GTS.

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• Perform the simulation method while checking the Data List.

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PROCEDURE

1.

CLEAR DTC

(a) Turn the ignition switch to ON, and wait for at least 60 seconds.

(b) Clear the DTCs stored in memory.

Body Electrical > SRS Airbag > Clear DTCs

(c) Turn the ignition switch off.

NEXT

2.

CHECK DTC

(a) Turn the ignition switch to ON, and wait for at least 60 seconds.

(b) Check for DTCs.

Body Electrical > SRS Airbag > Trouble Codes

Result	Proceed to
B00731A is output	A
B00731A is not output	B

B

USE SIMULATION METHOD TO CHECK

A

3.	CHECK CONNECTION OF CONNECTORS

(a) Turn the ignition switch off.

(b) Disconnect the cable from the negative (-) battery terminal, and wait for at least 60 seconds.

(c) Check that the connectors are properly connected to the rear seat outer belt assembly LH and airbag ECU assembly.

OK:

The connectors are properly connected.

NG

CONNECT CONNECTORS PROPERLY

OK

4.	CHECK CONNECTORS

(a) Disconnect the airbag ECU assembly connector.

*1 Rear Seat Outer Belt Assembly LH *2 Airbag ECU Assembly *3 Wire Harness

(b) Disconnect the rear seat outer belt assembly LH connector.

(c) Check that the terminals of the connectors are not deformed or damaged.

OK:

The terminals are not deformed or damaged.

(d) Check that the connectors are not loose, deformed or damaged.

OK:

The connector locking button is not disengaged, and the claw of the lock is not deformed or damaged.

(e) Check that the short springs of the activation prevention mechanism of the wire harness connector are not deformed or damaged.

OK:

The short springs are not deformed or damaged.

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

5.

CLEAR DTC

(a) Connect the airbag ECU assembly connector.

*1 Rear Seat Outer Belt Assembly LH *2 Airbag ECU Assembly *3 Wire Harness *a Front view of wire harness connector (to Rear Seat Outer Belt Assembly LH)

(b) Connect SST (resistance: 2.1 Ω) to connector C.

CAUTION:

Never connect the tester to the rear seat outer belt assembly LH for measurement, as this may lead to a serious injury due to pretensioner deployment.

NOTICE:

• Do not forcibly insert SST into the terminals of the connector when connecting SST.
• Insert SST straight into the terminals of the connector.

SST: 09843-18061

(c) Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

(d) Turn the ignition switch to ON, and wait for at least 60 seconds.

(e) Clear the DTCs stored in memory.

Body Electrical > SRS Airbag > Clear DTCs

(f) Turn the ignition switch off.

NEXT

6.	CHECK REAR SEAT OUTER BELT ASSEMBLY LH

(a) Turn the ignition switch to ON, and wait for at least 60 seconds.

(b) Check for DTCs.

Body Electrical > SRS Airbag > Trouble Codes

Result	Proceed to
B00731A is not output	A
B00731A is output	B

HINT:

Codes other than DTC B00731A may be output at this time, but they are not related to this check.

(c) Turn the ignition switch off.

(d) Disconnect the cable from the negative (-) battery terminal, and wait for at least 60 seconds.

(e) Disconnect SST from connector C.

A

REPLACE REAR SEAT OUTER BELT ASSEMBLY LH

B

7.	CHECK HARNESS AND CONNECTOR

(a) Disconnect the airbag ECU assembly connector.

*1	Rear Seat Outer Belt Assembly LH
*2	Airbag ECU Assembly
*3	Wire Harness
*a	Front view of wire harness connector (to Rear Seat Outer Belt Assembly LH)
	Release the activation prevention mechanism

(b) Release the activation prevention mechanism built into connector B.

HINT:

Click here

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection	Condition	Specified Condition
O5-1 (RL+) - O5-2 (RL-)	Always	1 MΩ or higher

(d) Restore the released activation prevention mechanism of connector B to its original condition.

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

8.

CLEAR DTC

(a) Connect the airbag ECU assembly connector.

*1 Rear Seat Outer Belt Assembly LH *2 Airbag ECU Assembly

(b) Connect the rear seat outer belt assembly LH connector.

(c) Connect the cable to the negative (-) battery terminal, and wait for at least 2 seconds.

(d) Turn the ignition switch to ON, and wait for at least 60 seconds.

(e) Clear the DTCs stored in memory.

Body Electrical > SRS Airbag > Clear DTCs

(f) Turn the ignition switch off.

NEXT

9.

CHECK DTC

(a) Turn the ignition switch to ON, and wait for at least 60 seconds.

(b) Check for DTCs.

Body Electrical > SRS Airbag > Trouble Codes

Result	Proceed to
B00731A is not output	A
B00731A is output	B

HINT:

Codes other than DTC B00731A may be output at this time, but they are not related to this check.

A

USE SIMULATION METHOD TO CHECK

B

REPLACE AIRBAG ECU ASSEMBLY

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