Toyota Corolla Cross: Load Sensor for Occupant Detection System Circuit Voltage Below Threshold (B179316)

DESCRIPTION

• *: The front occupant classification sensor LH and rear occupant classification sensor LH are built into the front seat cushion spring sub-assembly RH.

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.

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  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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• Inspect the fuses for circuits related to this system before performing the following procedure.

HINT:

• If it is difficult to perform troubleshooting (wire harness inspection), remove the front passenger seat installation bolts to see under the seat cushion.
• In the above case, lift and hold the seat so that it does not fall down. Hold the seat only as necessary because holding the seat for a long period of time may cause seat rail deformation.

PROCEDURE

(a) Turn the ignition switch off.

(b) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 60 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

(c) Check that the connectors are properly connected to the airbag ECU assembly, front occupant classification sensor LH and rear occupant classification sensor LH.

OK:

The connectors are properly connected.

NG

CONNECT CONNECTORS PROPERLY

OK

(a) Disconnect the connectors from the airbag ECU assembly, front occupant classification sensor LH and rear occupant classification sensor LH.

(b) Check that the terminals of the connectors are not deformed or damaged. OK: The terminals of the connectors are not deformed or damaged.

*1 Front Occupant Classification Sensor LH *2 Rear Occupant Classification Sensor LH *3 Airbag ECU Assembly *4 Wire Harness

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

(a) Disconnect the connector from the airbag ECU assembly.

(b) Connect the cable to the negative (-) battery terminal.

(c) Turn the ignition switch to ON.

(d) Operate all components of the electrical systems (defogger, wipers, headlights, heater blower, etc.).

(e) Measure the voltage according to the value(s) in the table below. Standard Voltage: Tester Connection Switch Condition Specified Condition I47-36 (IGR) - Body ground Ignition switch ON 8 to 16 V Result: Proceed to OK NG

*a Front view of wire harness connector (to Airbag ECU Assembly)

(f) Turn the ignition switch off.

(g) Disconnect the cable from the negative (-) battery terminal.

CAUTION:

Wait at least 60 seconds after disconnecting the cable from the negative (-) battery terminal to disable the SRS system.

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

(a) Measure the resistance according to the value(s) in the table below. Standard Resistance: Tester Connection Condition Specified Condition O17-24 (SVC) - Other terminals and body ground Always 10 kΩ or higher j16-1 (SVC) - Other terminals and body ground Always 10 kΩ or higher j17-1 (SVC) - Other terminals and body ground Always 10 kΩ or higher

*1 Front Occupant Classification Sensor LH *2 Rear Occupant Classification Sensor LH *3 Airbag ECU Assembly *4 Wire Harness *a Front view of wire harness connector (to Airbag ECU Assembly) *b Front view of wire harness connector (to Front Occupant Classification Sensor LH) *c Front view of wire harness connector (to Rear Occupant Classification Sensor LH)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

(a) Connect the connectors to the airbag sensor assembly.

(b) Connect the cable to the negative (-) auxiliary battery terminal.

(c) Turn the ignition switch to ON.

(d) Measure the voltage according to the value(s) in the table below. Standard Voltage: Tester Connection Switch Condition Specified Condition j16-1 (SVC) - Body ground Ignition switch ON 6.2 V or higher j17-1 (SVC) - Body ground Ignition switch ON 6.2 V or higher Result: Proceed to OK NG

*1 Front Occupant Classification Sensor LH *2 Rear Occupant Classification Sensor LH *3 Airbag Sensor Assembly *4 Wire Harness *a Front view of wire harness connector (to Front Occupant Classification Sensor LH) *b Front view of wire harness connector (to Rear Occupant Classification Sensor LH)

(e) Turn the ignition switch off.

(f) Disconnect the cable from the negative (-) auxiliary battery terminal.

CAUTION:

Wait at least 60 seconds after disconnecting the cable from the negative (-) auxiliary battery terminal to disable the SRS system.

OK

REPLACE FRONT SEAT CUSHION SPRING SUB-ASSEMBLY RH

NG

REPLACE AIRBAG ECU ASSEMBLY

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