Toyota RAV4 (XA40) 2013-2018 Service Manual: Abs warning light remains on
Description
If any of the following conditions are detected, the abs warning light remains on:
- The ecu connectors are disconnected from the skid control ecu.
- There is a malfunction in the skid control ecu internal circuit.
- There is an open or short in the wire harness between the combination meter and the skid control ecu.
Hint:
The intelligent tester may not be used when there is a malfunction in the skid control ecu.
Wiring diagram
Inspection procedure
- Check can communication system
- Check if the can communication system dtc is output (see page ca-34).
Result 
- Inspect skid control ecu connector
- Check if the skid control ecu connector is properly installed.
Ok: the skid control ecu connector is properly installed.
- Check wire harness (skid control ecu - battery and body ground)
- Disconnect the a19 ecu connector.
- Measure the resistance of the wire harness side connector.
Standard resistance 
- Measure the voltage of the wire harness side connector.
Standard voltage 
- Perform active test by intelligent tester (abs warning light)
- Select the active test, generate a control command, and then check that the abs warning light operates.
Ok: the abs warning light is turned on or off.
Hint:
When the abs warning light remains illuminated, opens in the wire harness of the combination meters or abnormalities in the meter circuit should be considered.
Replace abs and traction actuator assembly
Control module communication bus off
Description
Inspection procedure
The skid control ecu inputs the signals from the ecm, steering angle sensor,
and yaw rate and
acceleration sensor via can communication system.
Ch ...
Abs warning light does not come on
Wiring diagram
Refer to the abs warning light circuit (see page bc-135).
Inspection procedure
Check can communication system
Check if the can communication system dtc is output
(see page ...
Other materials:
Dtc check / clear
Check dtc (using sst (check wire))
Check the dtcs (present trouble code).
Turn the ignition switch on, and wait for
approximately 60 seconds.
Using sst, connect terminals 13(tc) and 4(cg)
of the dlc3.
Sst 09843-18040
Notice:
Connect the terminals to the correct
positio ...
Ecm power source circuit
Description
When the ignition switch is turned on, the battery voltage is applied to the
igsw of the ecm. The output
signal from the mrel terminal of the ecm causes a current to flow to the coil,
closing the contacts of the
integration relay (efi main relay) and supplying power to either term ...
Diagnosis system
Description
When troubleshooting on-board diagnostic (obd
ii) vehicles, the vehicle must be connected to the
obd ii scan tool (complying with sae j1987).
Various data output from the vehicle's ecm can
then be read.
Obd ii regulations require that the vehicle's onboard
computer ...
