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:
System voltage
Description
The battery supplies electricity to the ecm even when the ignition switch is
in the off position. This
power allows the ecm to store data such as dtc history, freeze frame data and
fuel trim values. If the
battery voltage falls below a minimum level, the memory is cleared and ...
Evaporative emission control system pressure sensor
Dtc summary
Hint:
The canister pressure sensor is built into the canister pump module.
Description
The description can be found in the evap (evaporative emission) system (see
page es-335).
Monitor description
Dtc p0450: canister pressure sensor abnormal fluctuation
If t ...
Throttle / pedal position sensor
Hint:
These dtcs relate to the accelerator pedal position (app) sensor.
Description
Hint:
This etcs (electronic throttle control system) does not use a throttle cable.
The app sensor is mounted on the accelerator pedal bracket and has 2 sensor
circuits: vpa (main) and
vpa2 (sub). This ...
