Toyota RAV4 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

1. Perform active test by intelligent tester

1. Connect the intelligent tester (with can vim) to the dlc3.
2. Turn the ignition switch to the on position and press the intelligent tester main switch on.
3. Select the item below in the active test and then check the relay operation.

Ok: front fog light comes on.

2. Check taillight

1. Check that the taillight comes on when the light control switch is on (tail).

Ok: taillight comes on.

3. Inspect fuse (fr fog)

1. Remove the fr fog fuse from the instrument panel junction block.
2. Measure the resistance of the fuses.

Standard resistance: below 1

4. Inspect fog light bulb

1. Remove the fog light bulb.
2. 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.

5. Inspect front fog light relay (marking: fr fog)

1. Remove the front fog light relay from the no. 6 Relay block.
2. Measure the resistance of the relay.

Standard resistance

6. Check wire harness (battery - main body ecu)

1. Disconnect the e17 ecu connector.
2. Measure the voltage of the wire harness side connector.

Standard voltage

7. Check wire harness (front fog light relay - battery)

1. Remove the front fog light relay from the no. 6 Relay block.
2. Measure the voltage of the relay block.

Standard voltage

8. Check wire harness (front fog light relay - front fog light and body ground)

1. Remove the front fog light relay from the no. 6 Relay block.
2. Disconnect the a11 and a28 front fog light connectors.
3. Measure the resistance of the wire harness side connectors.

Standard resistance

Replace instrument panel junction block (main body ecu)

9. Check wire harness (dimmer switch - main body ecu and body ground)

1. Disconnect the e12 headlight dimmer switch connector.
2. Disconnect the e17 main body ecu connector.
3. Measure the resistance of the wire harness side connectors.

Standard resistance

10. Inspect fog light switch

1. Remove the headlight dimmer switch.
2. Measure the resistance of the switch.

Standard resistance

Repair or replace harness and connector (headlight dimmer switch - body ground)