A large number of ecu controlled systems are used in the rav4. In general, ecu controlled systems are considered to be very intricate, requiring a high level of technical knowledge to troubleshoot. However, most problem checking procedures only involve inspecting the ecu controlled system's circuits one by one. An adequate understanding of the system and a basic knowledge of electricity is enough to perform effective troubleshooting, accurate diagnoses and necessary repairs.
For using intelligent tester

Connect the cable of the intelligent tester to the dlc3, turn the ignition switch on and attempt to use the tester. If the display indicates that a communication error has occurred, there is a problem either with the vehicle or with the tester.
* If communication is normal when the tester is connected to another vehicle, inspect the dlc3 of the original vehicle.
* If communication is still not possible when the tester is connected to another vehicle, the problem may be in the tester itself. Consult the service department listed in the tester's instruction manual.
Catalyst system efficiency below threshold (bank 1)
Monitor description
The ecm uses sensors mounted in front of and behind the three-way catalytic
converter (twc) to
monitor its efficiency.
The first sensor, the air-fuel ratio (a/f) sensor, sends pre-catalyst
information to the ecm. The second
sensor, the heated oxygen (ho2) sensor, se ...
Removal
Disconnect cable from negative battery
terminal
Caution:
Wait at least 90 seconds after disconnecting the
cable from the negative (-) battery terminal to
prevent airbag and seat belt pretensioner activation.
Remove no. 1 Engine under cover
Remove front fender apron rh
Remove radia ...
Mass air flow circuit range / performance problem
Description
Refer to dtc p0100 (see page es-86).
Monitor description
The maf meter is a sensor that measures the amount of air flowing through the
throttle valve. The ecm
uses this information to determine the fuel injection time and to provide an
appropriate air-fuel ratio. Inside
...