Toyota RAV4 Service Manual: Ecu power source circuit
Description
This is the power source for the tire pressure warning ecu.
Wiring diagram
Inspection procedure
Notice:
It is necessary to register an id code after replacing the tire pressure monitor valve and/or the tire pressure warning ecu (see page tw-9).
- Inspect fuse (ecu-ig1)
- Remove the ecu-ig1 fuse from the instrument panel junction block.
- Measure the resistance of the fuse.
Standard resistance:
below 1 
- Inspect ig1 relay
- Remove the ig1 relay from the instrument panel junction block.
- Measure the resistance of the relay.
Standard resistance
- Inspect wire harness (ecu - battery and body ground)
- Disconnect the e56 ecu connector.
- Measure the voltage of the wire harness side connector.
Standard voltage 
- Measure the resistance of the wire harness side connector.
Standard resistance 
Proceed to next circuit inspection shown in problem symptoms table
Tire pressure warning light circuit
Description
If the tire pressure warning ecu detects trouble, the tire pressure warning
light turns on and tire pressure
monitor is canceled at the same time. At this time, the ecu records a dtc i ...
Tire pressure warning receiver (w/ antenna)
Components
...
Other materials:
Passenger airbag on / off indicator circuit malfunction
Description
The passenger airbag on / off indicator circuit consists of the center airbag
sensor and the heater
control panel*1 or *2.
This circuit indicates the operation condition of the front passenger airbag,
the front passenger side airbag
and passenger side seat belt pretensioner ...
Oxygen (a/f) sensor pumping current circuit
Description
Refer to dtc p2195 (see page es-292).
Monitor description
The air-fuel ratio (a/f) sensor varies its output voltage in proportion to
the air-fuel ratio. If the a/f sensor
impedance (alternating current resistance) or output voltage deviates greatly
from the standard range ...
Problem symptoms table
When a "normal" code is output during a dtc check but
the problem is still occurring, use the problem symptoms
table. The suspected areas (circuits or parts) for each
problem symptom are in the table. The suspected areas
are listed in order of probability. A description of each of
the ...