Toyota RAV4 (XA40) 2013-2018 Service Manual: Back-up power source circuit
Description
This is the back-up power source circuit for the air conditioning amplifier. Power is supplied even when the ignition switch is turned off and is used for functions such as the diagnostic trouble code memory.
wiring diagram
Inspection procedure
- Inspect fuse (ecu-b2)
- Remove the ecu-b2 fuse from the engine room no. 2 Relay block.
- Measure the resistance of the fuse.
Standard resistance:
below 1 
- Check wire harness (air conditioning amplifier - battery)
- Disconnect the e37 amplifier connector.
- Measure the voltage of the wire harness side connector.
Standard voltage
- Check wire harness (air conditioning amplifier - body ground)
- Disconnect the e37 amplifier connector.
- Measure the resistance of the wire harness side connector.
Standard resistance
Proceed to next circuit inspection shown in problem symptoms table
Ig power source circuit
Description
This is the main power source supplied to the air conditioning amplifier when
the ignition switch is on
(ig). This power source is used for operating components, such as the air
cond ...
Other materials:
Control module communication bus off
Description
The power steering ecu receives signals from the ecm and the skid control ecu
via the can
communication system.
Hint:
When 2 or more dtcs starting with [u] are output simultaneously, inspect
the connectors and wire
harness of each ecu.
If dtc u0105/41 is output, fi ...
All doors cannot be locked / unlocked simultaneously
Description
The main body ecu receives switch signals from the door control switch on the
power window regulator
master switch, door control switch and driver side door key cylinder, and
activates the door lock motor on
each door accordingly.
Wiring diagram
Inspection procedure
Perf ...
Operation check
Inspect driver side seat belt warning light
Turn the ignition switch on.
When the driver seat belt is not fastened, check that
the driver seat belt warning light on the combination
meter blinks.
When the driver seat belt is fastened, check that the
driver seat belt warning light o ...
