Toyota RAV4 (XA40) 2013-2018 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:
Ambient temperature sensor circuit
Description
The ambient temperature sensor is installed in the front part of the
condenser to detect the ambient
temperature and control the air conditioner. The sensor is connected to the
combination meter and
detects fluctuations in the ambient temperature. This data is used for
contr ...
System too
Description
The fuel trim is related to the feedback compensation value, not to the basic
injection time. The fuel trim
consists of both the short-term and the long-term fuel trims.
The short-term fuel trim is fuel compensation that is used to constantly
maintain the air-fuel ratio at
...
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.
Disconnect connectors a and c, and measure
the resistance
Standard resistance (fig. 6)
Hint:
Measure ...
