Airbag System Source Voltage Drop

Restraints. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35
Supplemental Restraint System. Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35

DESCRIPTION

WIRING DIAGRAM

INSPECTION PROCEDURE

CHECK WIRE HARNESS (CENTER AIRBAG SENSOR ASSEMBLY - BATTERY)

CHECK WIRE HARNESS (CENTER AIRBAG SENSOR ASSEMBLY - BODY GROUND)

CHECK SRS WARNING LIGHT

AIRBAG SYSTEM - Source Voltage Drop


DESCRIPTION

The SRS is equipped with a voltage-increase circuit (DC-DC converter) in the center airbag sensor in case the source voltage drops.
When the source voltage drops, the voltage-increase circuit (DC-DC converter) functions to increase the voltage of the SRS to a normal working level.
A malfunction in this circuit is displayed differently from other codes, in the fact that no DTCs are recorded. With a normal system code present, the source voltage drop is indicated when the SRS warning light comes on.
A malfunction in this circuit is not recorded in the center airbag sensor.
The SRS warning light automatically goes off when the source voltage returns to normal.

WIRING DIAGRAM


Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.Supplemental Restraint System.Airbag System.Airbag System  Source Voltage Drop


INSPECTION PROCEDURE

1.CHECK WIRE HARNESS (CENTER AIRBAG SENSOR ASSEMBLY - BATTERY)
Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.Supplemental Restraint System.Airbag System.Airbag System  Source Voltage Drop
  1. Turn the ignition switch off.

  1. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

  1. Disconnect the E49 connector from the center airbag sensor.

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

  1. Turn the ignition switch on (IG).

  1. Measure the voltage of the wire harness side connector.

    Standard voltage:
    Tester Connection
    Specified Condition
    E49-21 (IG2) - Body ground
    11 to 14 V


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR, CHARGING SYSTEM AND BATTERY
OK


2.CHECK WIRE HARNESS (CENTER AIRBAG SENSOR ASSEMBLY - BODY GROUND)
Toyota Rav4. Aca30, 33, 38 Gsa33 Zsa30, 35.Supplemental Restraint System.Airbag System.Airbag System  Source Voltage Drop
  1. Measure the resistance of the wire harness side connector.

    Standard resistance:
    Tester Connection
    Specified Condition
    E49-25 (E1) - Body ground
    Below 1 Ω
    E49-26 (E2) - Body ground
    Below 1 Ω


NG
REPAIR OR REPLACE HARNESS AND CONNECTOR
OK


3.CHECK SRS WARNING LIGHT
  1. Turn the ignition switch off.

  1. Disconnect the cable from the negative (-) battery terminal, and wait for at least 90 seconds.

  1. Connect the E49 center airbag sensor connector.

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

  1. Turn the ignition switch on (IG), and wait for at least 6 seconds.

  1. Operate all components of the electrical system (defogger, wiper, headlight, heater, blower, etc.) and check that the SRS warning light does not come on.

    OK:
    SRS warning light does not come on.


NG
REPLACE CENTER AIRBAG SENSOR ASSEMBLY
OK

END