Toyota RAV4 > Chassis electrical system > Airbag system — general information

Airbag system — general information

1. All models are equipped with a Supplemental Restraint System (SRS), more commonly known as an airbag. This system is designed to protect the driver, and the front seat passenger, from serious injury in the event of a head-on or frontal collision. It consists of airbag sensors mounted in the front, sides and a sensing/diagnostic module mounted in the center of the vehicle, near the floor console.

Components and operation Airbag modules

2. The airbag modules consist of a housing incorporating the cushion (airbag) and inflator unit. The inflator assembly is mounted on the back of the housing over a hole through which gas is expelled, inflating the bag almost instantaneously when an electrical signal is sent from the system. The specially wound wire on the driver’s side that carries this signal to the driver’s module is called a spiral cable. The spiral cable is a flat, ribbon-like electrically conductive tape that is wound many times so that it can transmit an electrical signal regardless of steering wheel position. Airbag modules are located in the steering wheel, on the passenger’s side above the glove box, at the upper side of each front seat (side-impact airbags) and head-level airbags located along the roof rails (side curtain airbags). The side-impact airbag modules are mounted inside of the seats, and the seat must be disassembled to gain access to the modules.

Seat belt retractors

3. The seat belt retractors are a pyrotechnic (explosive) unit, which operate both the lap and shoulder belts. During an impact that would trigger the airbag system, the airbag control unit also triggers the seat belt retractors. When the pyrotechnic charges go off, they accelerate the retractors to instantly take up any slack in the seat belt system to more fully prepare the driver and front seat passenger for impact. This pulls the passenger (and driver) back into their seat at the same instant as the airbag module deploys the airbag. This softens the impact into the airbag to further dissipate the collision’s energy.

Warning: Never strike the pillars or floorplan with a hammer or use an impact-driver tool in these areas unless the system is disabled.

Control unit and sensors

4. The sensing/diagnostic control unit contains an on-board microprocessor which monitors the operation of the system, and the crash sensors. The crash sensors are located in the front and sides of the vehicle. It checks this system every time the vehicle is started, causing the «AIRBAG» light to illuminate for five seconds, then go off, if the system is operating properly. If there is a fault in the system, the light may not come on at all, the light will go on and continue, either illuminated steadily or blinking, and the unit will store fault codes indicating the nature of the fault.


5. For the airbag(s) to deploy, the impact sensor(s) must be activated. When this condition occurs, the circuit to the airbag inflator is closed and the airbag inflates.

Self-diagnosis system

6. A self-diagnosis circuit in the SRS unit displays a light on the instrument panel when the ignition switch is turned to the on position. If the system is operating normally, the light should go out after about five seconds. If the light doesn’t come on, or doesn’t go out after a short time, or if it comes on while you’re driving the vehicle, or if it blinks at any time, there’s a malfunction in the SRS system. Has it inspected and repaired as soon as possible? Do not attempt to troubleshoot or service the SRS system yourself. Even a small mistake could cause the SRS system to malfunction when you need it.

Servicing components near the SRS system

7. Nevertheless, there are times when you need to remove the steering wheel, radio or service other components on or near the dashboard. At these times, you’ll be working around components and wire harnesses for the SRS system.

Warning: Do not use electrical test equipment on airbag system wires; it could cause the airbag(s) to deploy. ALWAYS DISABLE THE SRS SYSTEM BEFORE WORKING NEAR THE SRS SYSTEM COMPONENTS OR RELATED WIRING.

Disabling the SRS system

Warning: Any time you are working in the vicinity of airbag wiring or components, DISABLE THE SRS SYSTEM.

Warning: An auxiliary voltage input device (memory saver) must not be used when working near airbag system components.

8. To disable the airbag system, perform the following steps:

  1. Turn the steering wheel to the straight-ahead position and turn the ignition switch to the Lock position, then remove the key.
  2. Disconnect the negative battery cable (see Engine electrical systems).
  3. Wait at least two minutes to allow the back-up power supply to become depleted before working around any airbag system component
  4. Before touching any airbag system component, ground yourself to a metal part of the vehicle to discharge any static electricity built up in your body.

Enabling the system

9. To enable the airbag system, perform the following steps:

  1. Turn the ignition switch to the on position.
  2. Make sure nobody is inside the vehicle.
  3. Connect the negative battery cable.
  4. Turn the ignition to the Off position, then with your body out of the path of the airbag, turn the ignition switch to the on position. Confirm that the airbag warning light is functioning properly.
  5. Take the vehicle to a dealer service department or other qualified repair facility and have the airbag system checked and the diagnostic light canceled, if it remains lit.

Component removal and installation

Warning: Whenever handling an airbag module, always keep the airbag opening (the trim side) pointed away from your body. Never place the airbag module on a workbench or other surface with the airbag opening (upholstered side) facing the surface. Always place the airbag module in a safe location with the airbag opening facing up.

Warning: Never dispose of a live airbag module. Return it to a dealer service department or other qualified repair shop for safe deployment and disposal.

Note: Always wait at least 90 seconds after disconnecting the negative battery terminal before working on any airbag component.

Airbag control module

Note: The airbag control module can be referred to by several different names, depending on whom you’re talking to. It is sometimes referred to as a crash box, smart box, air bag controller, or the restraint control module. All of which refer to the same component. Never use a salvage controller. Always replace with a new (unprogrammed) module.

10. Remove the center console (see Body).

11. Locate the airbag control module and remove the fasteners securing it to the vehicle (see illustration).

i. 11 Airbag control module fasteners

Toyota RAV4 Chassis electrical system Airbag control module fasteners

12. Remove the fasteners, then disconnect the electrical connectors (see illustration).

i. 12 Airbag controller electrical connection removal procedure

A Push down on the white tab slightly
B Now swing the white tab toward the middle of the airbag control module connection to remove the connector

Toyota RAV4 Chassis electrical system Airbag controller electrical connection removal procedure

Caution: Proper disconnection of the airbag module is critical, otherwise you can damage the connector (see illustration).

Note: After replacing the airbag module it will need to be programmed. This will require a factory level scanner. Take your vehicle to the appropriate repair facility to have this procedure performed.

Driver’s airbag module and spiral cable removal

13. Refer to Suspension and steering, Steering wheel -removal and installation, for the driver’s side airbag module and spiral cable removal and installation procedures.

Note: The spiral cable is also referred to as the clock spring.

Passenger’s airbag module

14. Disarm the airbag system as describes previously in this Section.

15. Remove the glove box (see Body), then unplug the electrical connector and remove the airbag module mounting fasteners. Remove the upper instrument panel (see Tune-up and routine maintenance1) and module out as a unit. Warning: Slightly bend the mounting hooks back and lift out the front passenger’s airbag rearwards. Be sure to heed the precautions outlined previously in this Section.

16. Installation is the reverse of removal. Tighten the airbag module mounting fasteners to 15 ft-lbs. (20 Nm).

Knee bolster module

17. The knee bolster trim and airbag are basically one component (see illustrations). Follow the illustrations for details on the removal of the knee bolster module.

i. 17a Remove the upper fasteners…

Toyota RAV4 Chassis electrical system Remove the upper fasteners

i. 17b… then the two lower fasteners

Toyota RAV4 Chassis electrical system |

i. 17c Pry the knee bolster module off with a flat trim tool

Toyota RAV4 Chassis electrical system Pry the knee bolster module off with a flat trim tool

i. 17d Disconnect the electrical connection and remove the module

Toyota RAV4 Chassis electrical system Disconnect the electrical connection and remove the module

Other airbag system components (front seat cushion airbag, side curtain airbags, seat belt retractors, occupant detection system)

18. It is not advisable to tamper with any of these components.

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