Toyota RAV4 manuals

Toyota Sienna Service Manual: SRS Warning Light Remains ON

DESCRIPTION

The SRS warning light is located on the combination meter assembly.

When the SRS is normal, the SRS warning light comes on for approximately 6 seconds after the ignition switch is turned from the LOCK position to ON position, and then goes off automatically.

If there is a malfunction in the SRS, the SRS warning light comes on to inform the driver of a problem.

When terminals TC and CG of the DLC3 are connected, the DTC is displayed by blinking of the SRS warning light.

The SRS is equipped with a voltage-increase circuit (DC-DC converter) in the center airbag sensor assembly in case the source voltage drops.

When the battery voltage drops, the voltage-increase circuit (DC-DC converter) functions to increase the voltage of the SRS to normal voltage.

A malfunction in this circuit is not recorded in the center airbag sensor assembly. The SRS warning light automatically goes off when the source voltage returns to normal.

The signal to illuminate the SRS warning light is transmitted from the center airbag sensor assembly to the combination meter assembly through the multiplex communication system.

WIRING DIAGRAM

WIRING DIAGRAM

WIRING DIAGRAM

INSPECTION PROCEDURE

1 CHECK MULTIPLEX COMMUNICATION SYSTEM

  1. Check if the multiplex communication DTC is output.

HINT: The center airbag sensor assembly of this system is connected to the multiplex communication system.

Therefore, before starting troubleshooting, make sure to check that there is no trouble in the multiplex communication system.

OK: The Multiplex communication system DTC is not output.

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS

2 CHECK BATTERY

  1. Measure the voltage of the battery.

Standard voltage: 11 to 14 V

CHECK AND REPLACE BATTERY OR CHARGING SYSTEM

3 CHECK CONNECTORS

  1. Turn the ignition switch to the LOCK position.
  2.  Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
  3.  Check that the connectors are properly connected to the center airbag sensor assembly and combination meter assembly.

OK: The connectors are properly connected

CONNECT CONNECTORS

4 CHECK WIRE HARNESS (SOURCE VOLTAGE OF CENTER AIRBAG SENSOR ASSEMBLY)

CHECK WIRE HARNESS (SOURCE VOLTAGE OF CENTER AIRBAG SENSOR ASSEMBLY)

  1. Disconnect the connectors from the center airbag sensor assembly.
  2.  Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
  3.  Turn the ignition switch to the ON position.
  4.  Operate all components of the electrical system (defogger, wipers, headlight, heater blower, etc.).
  5.  Measure the voltage according to the value(s) in the table below.

Standard voltage

Standard voltage

  1. Turn the ignition switch to the LOCK position.
  2. Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

REPAIR OR REPLACE WIRE HARNESS

5 CHECK WIRE HARNESS (SOURCE VOLTAGE OF COMBINATION METER ASSEMBLY)

 CHECK WIRE HARNESS (SOURCE VOLTAGE OF COMBINATION METER ASSEMBLY)

  1. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
  2. Disconnect the connector from the combination meter assembly.
  3.  Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
  4.  Turn the ignition switch to the ON position.
  5.  Measure the voltage according to the value(s) in the table below.

Standard voltage

  1. Turn the ignition switch to the LOCK position.
  2. Measure the resistance according to the value(s) in the table below.

Standard resistance

Standard resistance

REPAIR OR REPLACE WIRE HARNESS

6 CHECK SRS WARNING LIGHT

  1. Turn the ignition switch to the LOCK position.
  2. Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
  3.  Connect the connector to the combination meter assembly.
  4.  Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
  5.  Turn the ignition switch to the ON position.
  6.  Check the SRS warning light condition.

OK: After the primary check period, SRS warning light goes off for approximately 10 seconds, and remains on. HINT: The primary check period shows approximately 6 seconds after the ignition switch is turned to the ON position.

REPLACE COMBINATION METER ASSEMBLY

REPLACE CENTER AIRBAG SENSOR ASSEMBLY

Short to B+ in Rear Curtain Shield Squib LH Circuit
DTC B1638/86 Short to B+ in Rear Curtain Shield Squib LH Circuit DESCRIPTION The rear curtain shield squib LH circuit consists of the center airbag sensor assembly and the curtain shield airbag ...

SRS Warning Light does not Come ON
DESCRIPTION WIRING DIAGRAM INSPECTION PROCEDURE 1 CHECK BATTERY Measure the voltage of the battery. Standard voltage: 11 to 14 V CHECK AND REPLACE BATTERY OR CHARGING SYSTEM 2 CHECK CO ...

Other materials:

Terminals of ECU
1. CHECK POWER BACK DOOR ECU Disconnect the P13 and P14 ECU connectors, and check the voltage or resistance of each terminal of the wire harness side connectors If the result is not as specified, there may be a malfunction on the wire harness side. Reconnect the ECU connector ...

On-vehicle inspection
1. INSPECT CENTER AIRBAG SENSOR ASSEMBLY (VEHICLE NOT INVOLVED IN COLLISION)  Perform a diagnosis system check. 2. INSPECT CENTER AIRBAG SENSOR ASSEMBLY (VEHICLE INVOLVED IN COLLISION AND AIRBAG HAS NOT DEPLOYED)  Perform a diagnosis system check. 3. INSPECT CENTER AIRBAG ...

Transponder Chip Malfunction
DTC B2793 Transponder Chip Malfunction DESCRIPTION This DTC is output when a malfunction is found in the key during the key code registration or the key code is not registered normally. Replace the key when the key code registration is not performed normally and this DTC is detected. IN ...

В© 2011-2022 Copyright www.tsienna.net