Toyota RAV4 Service Manual: Check for open circuit
- For an open circuit in the wire harness in fig. 1, Check the resistance or voltage, as described below.
- Check the resistance.
- Disconnect connectors a and c, and measure the resistance between them.
Standard resistance (fig. 2)
Hint:
Measure the resistance while lightly shaking the wire harness vertically and horizontally.
If the results match the examples above, an open circuit exists between terminal 1 of connector a and terminal 1 of connector c.
- Disconnect connector b and measure the resistance between the connectors.
Standard resistance (fig. 3)
If the results match the examples
above, an
open circuit exists between terminal 1 of
connector b2 and terminal 1 of connector c.
- Check the voltage.
- In a circuit in which voltage is applied to the ecu
connector terminal, an open circuit can be
checked by conducting a voltage check.
With each connector still connected, measure the voltage between the body ground and these terminals (in this order): 1) terminal 1 of connector a, 2) terminal 1 of connector b, and 3) terminal 1 of connector c.
Standard voltage (fig. 4)
If the results match the examples
above, an
open circuit exists in the wire harness between
terminal 1 of connector b and terminal 1 of
connector c.
Basic inspection
When measuring resistance of
electronic parts
Unless otherwise stated, all resistance
measurements should be made at an ambient
temperature of 20°c (68°f). Resistance
measurements m ...
Check for short circuit
If the wire harness is ground shorted (fig. 5), Locate
the section by conducting a resistance check with
the body ground (below).
Check the resistance with the body ground.
Disconne ...
Other materials:
All-wheel drive lock
switch (awd models)
All-wheel drive lock mode can be used when a large amount of
drive power needs to be applied to all the wheels, such as when
the vehicle gets stuck in mud and you need to free it.
Press the switch.
The torque of the engine is distributed
to the rear wheels to the maximum
extent possible in
ac ...
Mass or volume air flow circuit
Description
The mass air flow (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 the appropriate air-fuel
ratio.
Inside the maf meter, there is a heated platinu ...
Emission control system
Parts location
System diagram
On-vehicle inspection
Check fuel cut rpm
Increase the engine speed to at least 3,500 rpm.
Use a sound scope to check for injector operating
noise.
Check that the operating sounds stop momentarily
and then resume when the t ...