Toyota RAV4 (XA40) 2013-2018 Service Manual: Srs warning light does not come on
Description
The srs warning light is located on the combination meter.
When the srs is normal, the srs warning light comes on for approximately 6 seconds after the ignition switch is turned from off to on, 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 the srs warning light.
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 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 . 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 to the combination meter through the multiplex communication system.
Wiring diagram
Inspection procedure
- Check battery
- Measure the voltage of the battery.
Standard voltage: 11 to 14 v
- Check connectors
- Turn the ignition switch off.
- Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
- Check that the e19 connectors are properly connected to the center airbag sensor and the combination meter.
Ok: the connectors are properly connected.
- Check wire harness (source voltage of combination meter)
- Turn the ignition switch off.
- Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
- Disconnect the connector from the combination meter.
- Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
- Turn the ignition switch on.
- Measure the voltage of the wire harness side connectors.
Standard voltage 
- Turn the ignition switch off.
- Measure the resistance of the wire harness side connectors.
Standard resistance 
- Check srs warning light
- Turn the ignition switch off.
- Disconnect the negative (-) terminal cable from the battery, and wait for at least 90 seconds.
- Connect the e19 connector to the combination meter.
- Connect the negative (-) terminal cable to the battery, and wait for at least 2 seconds.
- Turn the ignition switch on.
- Check the srs warning light condition.
Ok: the srs warning light does not come on.
Replace center airbag sensor assembly
Srs warning light remains on
Description
The srs warning light is located on the combination meter.
When the srs is normal, the srs warning light comes on for approximately 6
seconds after the ignition
switch is turned fro ...
Tc and cg terminal circuit
Description
Dtc output mode is set by connecting terminals tc and cg of the dlc3.
The dtcs are displayed by blinking the srs warning light.
Hint:
Make sure that dtc b1281 has not been output. ...
Other materials:
Pig power supply voltage malfunction
Description
When a problem occurs in the system, the power source relay circuit is shut
off to stop the power assist.
Wiring diagram
Inspection procedure
Read value of intelligent tester (pig power supply)
Connect the intelligent tester (with can vim) to the
dlc3.
Turn ...
Symptom simulation
Hint:
The most difficult case in troubleshooting is when no
problem symptoms occur. In such a case, a thorough
problem analysis must be carried out. A simulation of the
same or similar conditions and environment in which the
problem occurred in the customer's vehicle should be
carried out. No ...
Multiplex communication circuit
Description
The air conditioning amplifier communicates data with the ecm and combination
meter through the can
communication system.
Wiring diagram
Inspection procedure
Check dtc
Clear the dtc (see page ac-127).
Read the dtc (see page ac-127).
Result
Go to can ...
