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:
Precaution
Notice:
Perform the reset memory procedures (a/t
initialization) when replacing the automatic transaxle
assembly, engine assembly or ecm (see page ax-18).
Hint:
Reset memory cannot be completed by only reconnecting
the cable to the negative (-) battery terminal.
Caution:
When using compresse ...
How to proceed with troubleshooting
Hint:
Use these procedures to troubleshoot the seat belt
warning system.
*: Use the intelligent tester.
Vehicle brought to workshop
Inspect battery voltage
Standard voltage:
11 to 14 v
If the voltage is below 11 v, recharge or replace the battery
before proceeding.
...
Air-fuel ratio (a/f) and heated oxygen (ho2) sensor
heater monitors (front a/f and rear ho2 sensor type)
Preconditions
The monitor will not run unless:
The mil is off.
Drive pattern
Connect the intelligent tester to the dlc3.
Turn the ignition switch on.
Turn the tester on.
Clear dtcs (if set) (see page es-35).
Start the engine.
Allow the engine to idle for 10 minute ...
