Seat belt pretensioners

The driver and front passenger seat belt pretensioners are designed to be activated in response to a severe frontal impact.

When the sensor detects a severe frontal impact, the front seat belts are quickly drawn back by the retractors so that the belts snugly restrain the occupants.


• After inserting the tab, make sure the tab and buckle are locked and that the lap and shoulder portions of the belt and the seat belt extender are not twisted.

• Do not insert coins, clips, etc. in the buckle as this may prevent you from properly latching the tab and buckle.

• If the seat belt does not function normally, immediately contact your Toyota dealer. Do not use the seat until the seat belt is fixed, because it cannot protect an adult occupant or your child from death or serious injury.

The front passenger's seat belt pretension-er will not activate if no passenger is detected in the front passenger seat by the front passenger occupant classification system. However, the front passenger's seat belt pretensioner may activate if luggage is put on the seat, or the seat belt is buckled up regardless of the presence of an occupant in the seat. (As for the front passenger occupant classification system, see "Front passenger occupant classification system" on page 69 in this Section.)

The seat belt pretensioners and SRS air-bags may not operate together in all collisions.

Occupant Classification System

The seat belt pretensioner system consists mainly of the following components and their locations are shown in the illustration.

1. Front airbag sensors

2. SRS warning light

3. "AIRBAG ON" and "AIRBAG OFF" indicator lights

4. Front passenger's seat belt buckle switch

5. Front passenger occupant classification system (ECU and sensors)

6. Seat belt pretensioner assemblies

7. Airbag sensor assembly

The seat belt pretensioners are controlled by the airbag sensor assembly. The airbag sensor assembly consists of a safing sensor and airbag sensor.

When the seat belt pretensioners are activated, an operating noise may be heard and a small amount of non-toxic gas may be released. This does not indicate that a fire is occurring. This gas is normally harmless.

Once the seat belt pretensioners have been activated, the seat belt retractors remain locked.

Do not modify, remove, strike or open the seat belt pretensioner assemblies, airbag sensor or surrounding area or wiring. Failure to follow these instruction may prevent the seat belt preten-sioners from activating correctly, cause sudden operation of the system or disable the system, which could result in death or serious injury. Consult your Toyota dealer about any repair and modification.


Do not perform any of the following changes without consulting your Toyota dealer. Such changes can interfere with proper operation of the seat belt pretensioners in some cases.

♦ Installation of electronic devices such as a mobile two-way radio, cassette tape player or compact disc player

♦ Repairs on or near the front seat belt retractor assemblies

♦ Modification of the suspension system

♦ Modification of the front end structure

♦ Attachment of a grille guard (bull bar, kangaroo bar, etc.), snowplow, winches or any other equipment to the front end

♦ Repairs made on or near the front fenders, front end structure or console

This indicator comes on when the ignition key is turned to the "ON" position. It goes off after about 6 seconds. This means the seat belt pretensioners are operating properly.

This warning light system monitors the airbag sensor assembly, front airbag sensors, side and curtain shield airbag sensors, curtain shield airbag sensors, driver's seat position sensor, driver's seat belt buckle switch, front passenger occupant classification system, "AIRBAG ON" indicator light, "AIRBAG OFF" indicator light, front passenger's seat belt buckle switch, seat belt pretensioner assemblies, inflators, interconnecting wiring and power sources. (For details, see "Service reminder indicators and warning buzzers" on page 114 in Section 1-6.)

If any of the following conditions occurs, this indicates a malfunction of the airbags or seat belt pretensioners. Contact your Toyota dealer as soon as possible.

• The light does not come on when the ignition key is turned to the "ON" position or remains on for more than 6 seconds or flashes.

• The light comes on or starts flashing while driving.

• If any seat belt does not retract or can not be pulled out due to a malfunction or activation of the relevant seat belt pretensioner.

• The seat belt pretensioner assembly or surrounding area has been damaged.

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  • cedivar
    How to test passenger seat belt pretensioner sensor?
    8 years ago

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