Toyota RAV4 (XA40) 2013-2018 Service Manual: Front fog light circuit
Description
The main body ecu controls the front fog light relay (marking: fr fog) when a signal is received from the headlight dimmer switch.
Wiring diagram
Inspection procedure
- Perform active test by intelligent tester
- Connect the intelligent tester (with can vim) to the dlc3.
- Turn the ignition switch to the on position and press the intelligent tester main switch on.
- Select the item below in the active test and then check the relay operation.
Ok: front fog light comes on.
- Check taillight
- Check that the taillight comes on when the light control switch is on (tail).
Ok: taillight comes on.
- Inspect fuse (fr fog)
- Remove the fr fog fuse from the instrument panel junction block.
- Measure the resistance of the fuses.
Standard resistance:
below 1 
- Inspect fog light bulb
- Remove the fog light bulb.
- Connect the positive (+) lead from the battery to terminal 2 and the negative (-) lead to terminal 1, then check that the bulb illuminates.
Ok: bulb illuminates.
- Inspect front fog light relay (marking: fr fog)
- Remove the front fog light relay from the no. 6 Relay block.
- Measure the resistance of the relay.
Standard resistance 
- Check wire harness (battery - main body ecu)
- Disconnect the e17 ecu connector.
- Measure the voltage of the wire harness side connector.
Standard voltage 
- Check wire harness (front fog light relay - battery)
- Remove the front fog light relay from the no. 6 Relay block.
- Measure the voltage of the relay block.
Standard voltage 
- Check wire harness (front fog light relay - front fog light and body ground)
- Remove the front fog light relay from the no. 6 Relay block.
- Disconnect the a11 and a28 front fog light connectors.
- Measure the resistance of the wire harness side connectors.
Standard resistance 
Replace instrument panel junction block (main body ecu)
- Check wire harness (dimmer switch - main body ecu and body ground)
- Disconnect the e12 headlight dimmer switch connector.
- Disconnect the e17 main body ecu connector.
- Measure the resistance of the wire harness side connectors.
Standard resistance 
- Inspect fog light switch
- Remove the headlight dimmer switch.
- Measure the resistance of the switch.
Standard resistance 
Repair or replace harness and connector (headlight dimmer switch - body ground)
Headlight (hi-beam) circuit
Description
The body ecu controls the headlight relay, no. 2 Daytime running light relay
(marking: drl no. 2) And
no. 4 Daytime running light relay (marking: drl no. 4).
Wiring diagram
I ...
Turn signal light circuit
Description
The turn signal flasher relay (marking: flsh) in the main body ecu turns on
when it receives signals
from the headlight dimmer switch integrated with the turn signal switch, causing
...
Other materials:
Open in one side of can branch line
Description
If 2 or more ecus and/or sensors do not appear on the intelligent tester's
"bus check" screen via the
can vim, one side of the can branch wire may be open. (One side of the canh
[branch wire] /canl
[branch wire] of the ecu and/or sensor is open.)
Wiring diagram
...
Reassembly
Install evaporator temperature sensor
Notice:
If reusing the evaporator, do not insert the sensor to
a location where the sensor was previously inserted.
Insert the sensor within range c shown in the
illustration.
Install the evaporator temperature sensor as shown
in the illustrati ...
Fail-safe chart
Fail-safe function
When communication fails in any of the main wires
(communication lines) due to a short circuit or other
causes, the fail-safe function, which is specified for
each system, operates to prevent the system from
malfunctioning.
The table below shows the effects on e ...
