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:
Operating a bluetooth® enabled portable player
Power
Volume
Search playback
Next commands, random play
or back button
Repeat play
Fast-forwarding, rewinding or
selecting an album
Changing the audio source/
playback
Playback/pause
Previous commands
Selecting a track
Displaying text message
Selecting an album
P ...
Checking the coolant
The coolant level is satisfactory
if it is between the "FULL" and
"LOW" lines on the reservoir
when the engine is cold.
Reservoir cap
"FULL" line
"LOW" line
If the level is on or below the "LOW" line, add coolant up to the "FULL"
line.
â– Coolant selection
Only use "Toyota Super Long Life
Cool ...
Brake switch "B" circuit high
Description
The purpose of this circuit is to prevent the engine from stalling while
driving in the lock-up condition when
the brakes are suddenly applied.
When the brake pedal is depressed, this switch sends a signal to the ecm. Then
the ecm cancels the
operation of the lock-up clutch ...
