Air Bag Systems: Service Precautions

PRECAUTION

CAUTION:
- Do not use seat accessories (such as cushions or covers) that cover the front seat. Also, do not modify or replace the upholstery of the front seat. Doing so may prevent the front passenger airbag system from activating correctly, disable the system or cause the front passenger airbag to inflate accidentally, and result in death or serious injury.
- The vehicle is equipped with a Supplemental Restraint System (SRS), with consists of a steering pad, front passenger airbag, side airbag, curtain shield airbag, and front seat belt pretensioner. Failure to carry out service procedures in the correct sequence could cause the SRS parts to unexpectedly deploy and possibly lead to serious injuries, Further, if a mistake is made when servicing SRS parts, they may fail to operate when required. Before performing servicing (including installation/removal, inspection and replacement of parts), be sure to read the following precaution,
- Before starting work, wait at least 90 seconds after the ignition switch is turned OFF and after the cable of the negative (-) battery terminal is disconnected. (SRS parts are equipped with a backup power source. If work is started within 90 seconds of turning the ignition switch OFF and disconnecting the cable from the negative (-) battery terminal, SRS parts may deploy.)
- Do not expose the SRS parts directly to hot air or flames.

NOTE:
- Replace the occupant classification ECU, occupant classification sensor, seat cushion cover pad, seat cushion cover and seat cushion seat heater as a 5 part set (see supply set part no.).
- Malfunction symptoms of SRS parts are difficult to confirm. DTCs are the most important source of information when troubleshooting. During troubleshooting, always confirm DTCs before disconnecting the cable from the negative (-) battery terminal.
- For minor collisions where SRS parts do not deploy, always inspect the SRS parts.
- Before repair work, remove airbag sensors as necessary if any kind of impact is likely to occur to an airbag sensor during the operation.
- Never use SRS parts from another vehicle. When replacing SRS parts, replace them with new ones.
- Never disassemble or attempt to repair SRS parts
- If an SRS part has been dropped, or if there are any cracks, dents or other defects in the case, bracket or connector, replace the SRS part with a new one
- Use an ohmmeter/voltmeter with high impedance (10 k ohms/V minimum) for troubleshooting the electrical circuits.
- Information labels are attached to the periphery of SRS parts. Follow the cautions and instructions on the labels.
- After work on SRS parts is completed, perform the SRS warning light check.
- When the cable is disconnected from the negative (-) battery terminal, the memory settings of each system will be cleared. Because of this, be sure to write down the settings of each system before starting work. When work is finished, reset the settings of each system as before. Never use a backup power supply from outside the vehicle to avoid erasing the memory in a system.
- If the vehicle is equipped with a mobile communication system, refer to the Vehicle; Service Precautions.

HINT: In the airbag system, the center airbag sensor, front airbag sensors LH and RH, side airbag sensors LH and RH, and rear airbag sensors LH and RH are collectively referred to as the airbag sensors.

1. HANDLING PRECAUTIONS FOR AIRBAG SENSORS
a. Before starting the following operations, wait for at least 90 seconds after disconnecting the negative (-) terminal cable from the battery:
1. Replacement of the airbag sensors
2. Adjustment of the front / rear doors of a vehicle equipped with a side airbag and curtain shield airbag (fitting adjustment).

b. When connecting or disconnecting the airbag sensor connectors, ensure that each sensor is installed in the vehicle.
c. Do not use airbag sensors which have been dropped during the operation or transportation.
d. Do not disassemble the airbag sensors.

2. INSPECTION PROCEDURE FOR VEHICLE INVOLVED IN ACCIDENT
a. When the airbag has not deployed, confirm the DTCs by checking the SRS warning light. If there is any malfunction in the SRS airbag system, perform troubleshooting.
b. When any of the airbags have deployed, replace the airbag sensors and check the installation condition.

3. SRS CONNECTORS

Part 1:

Part 2:

a. SRS connectors are located as shown in the given illustration.

b. All connectors in the SRS, except the seat position airbag sensor connector, are colored yellow to distinguish them from other connectors. These connectors have special functions, and are specially designed for the SRS. All SRS connectors use durable gold-plated terminals, and are placed in the locations shown above to ensure high reliability.




1. Terminal twin-lock mechanism:
All connectors with a terminal twin-lock mechanism have a two-piece component consisting of a housing and a spacer. This design enables the terminal to be locked securely by two locking devices (the retainer and the lance) to prevent terminals from coming out.




2. Activation prevention mechanism:
All connectors with an activation prevention mechanism contain a short spring plate. When these connectors are disconnected, the short spring plate creates a short circuit by automatically connecting the positive (+) and negative (-) terminals of the squib.







3. Electrical connection check mechanism:
This mechanism electrically checks that the connectors are connected correctly and completely. The electrical connection check mechanism is designed so that the disconnection detection pin connects with the diagnosis terminals when the connector housing lock is locked.




4. Half connection prevention mechanism:
If the connector is not completely connected, the connector is disconnected due to the spring operation so that no continuity exists.




5. Connector lock mechanism:
Locking the connector lock button connects the connector securely.




4. DISCONNECTION OF CONNECTORS FOR STEERING PAD, FRONT PASSENGER AIRBAG ASSEMBLY, CURTAIN SHIELD AIRBAG ASSEMBLY AND FRONT SEAT OUTER BELT ASSEMBLY

HINT: Tape the screwdriver tip before use.

a. Release the lock button (yellow part) of the connector using a screwdriver (Procedure A).
b. Insert the screwdriver tip between the connector and the base, and then raise the connector (Procedure B).

5. CONNECTION OF CONNECTORS FOR STEERING PAD, FRONT PASSENGER AIRBAG ASSEMBLY (SIDE SQUIB), CURTAIN SHIELD AIRBAG ASSEMBLY AND FRONT SEAT OUTER BELT ASSEMBLY




a. Connect the connector.
b. Push down securely on the lock button (yellow part) of the connector. (When locking, a click sound can be heard.)

6. DISCONNECTION OF CONNECTOR FOR FRONT SEAT SIDE AIRBAG ASSEMBLY




a. Place a finger on the slider, slide the slider to release the lock, and then disconnect the connector.

7. CONNECTION OF CONNECTOR FOR FRONT SEAT SIDE AIRBAG ASSEMBLY




a. Connect the connector as shown in the illustration. (When locking, make sure that the slider returns to its original position and a click sound can be heard.)

HINT: When connecting, the slider will slide. Be sure not to touch the slider while connecting, as it may result in an insecure fit.

8. DISCONNECTION OF CONNECTORS FOR FRONT AIRBAG SENSOR, SIDE AND CURTAIN SHIELD AIRBAG SENSOR AND CURTAIN SHIELD AIRBAG SENSOR




a. While holding both sides of the outer connector locking sleeve, slide the sleeve in the direction shown by the arrow in the illustration.




b. When the connector lock is released, the connectors are disconnected.

HINT: Be sure to hold both sides of the sleeve. Holding the top and bottom will make disconnection difficult.

9. CONNECTION OF CONNECTORS FOR FRONT AIRBAG SENSOR, SIDE AND CURTAIN SHIELD AIRBAG SENSOR AND CURTAIN SHIELD AIRBAG SENSOR




a. Connect the connector as shown in the illustration (When locking, make sure that the outer connector locking sleeve returns to its original position and a click sound can be heard).

HINT: When connecting, the sleeve will slide. Be sure not to hold the sleeve while connecting, as it may result in an insecure fit.