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:
If the electronic key does
not operate properly
(vehicles with a
smart key system)
If communication between the electronic key and vehicle is
interrupted („_p. 107) Or the electronic key cannot be used
because the battery is depleted, the smart key system and wireless
remote control cannot be used. In such cases, the doors
can be opened and the engine can be started by follo ...
Ecm communication circuit malfunction
Description
The circuit is used to send trc and vsc control information from the skid
control ecu to the ecm, and
engine control information from the ecm to the skid control ecu.
Inspection procedure
Hint:
Check that the part numbers of the installed ecm and skid control ecu are
cor ...
Ecm communication stop mode (2005/11-2006/01)
Description
Wiring diagram
Inspection procedure
Notice:
Turn the ignition switch off before measuring the resistances of the
main wire and the branch
wire.
After the ignition switch is turned off, check that the key reminder
warning system and light
reminder warning system ...
