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.
Light control switch circuit
Description
This circuit detects the state of the headlight dimmer switch.
Wiring diagram
Inspection procedure
Read value of intelligent tester (main body ecu)
Connect the intelligent tester to the dlc3.
Turn the ignition switch on and press the intelligent
tester main switch on ...
Headlight switch
The headlights can be operated
manually or automatically.
Turning on the headlights
Operating the switch
turns on the lights as follows:
U.S.A. (Type A)
The side marker, parking,
tail, license plate, instrument
panel lights, and
daytime running lights turn on.
The headlights and all
light ...
Coolant
Replacement
Remove no. 1 Engine under cover
Drain engine coolant
Loosen the radiator drain cock plug.
Hint:
Collect the coolant in a container and dispose of it
according to the regulations in your area.
Remove the radiator reservoir cap.
Caution:
Do not remove the radiator ...