Toyota Corolla Cross Owners & Service Manuals

Toyota Corolla Cross: Front Fog Light Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls the front fog lights.

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Before replacing the main body ECU (multiplex network body ECU), refer to Registration.
  • First perform the communication function inspections in How to Proceed with Troubleshooting to confirm that there are no CXPI communication malfunctions before troubleshooting this symptom.

    Click here

PROCEDURE

1.

READ VALUE USING GTS

(a) Read the Data List according to the display on the GTS.

Body Electrical > Power Distribution Box > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Front Fog Light External Relay Input Signal

Front fog light external relay input

OFF or ON

OFF: Front fog light is not input

ON: Front fog light is input

-

Body Electrical > Power Distribution Box > Data List

Tester Display

Front Fog Light External Relay Input Signal

OK:

Display changes according to the front fog light switch operation.

NG

GO TO STEP 7

OK

2.

READ VALUE USING GTS

(a) Using the GTS, read the Data List.

Body Electrical > Power Distribution Box > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Front Fog Light External Relay Output Signal

Front fog light external relay output

OFF or ON

OFF: Front fog lights off

ON: Front fog lights on

-

Body Electrical > Power Distribution Box > Data List

Tester Display

Front Fog Light External Relay Output Signal

OK:

Display changes according to the front fog light switch operation.

NG

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

OK

3.

CHECK HARNESS AND CONNECTOR (POWER DISTRIBUTION BOX ASSEMBLY - BODY GROUND)

(a) Disconnect the 8C and 8B power distribution box assembly connectors.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

8C-25 - Body ground

Always

Below 1 Ω

8B-45 - Body ground

Always

Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

4.

INSPECT FOG FR RELAY

HINT:

Click here

NG

REPLACE FOG FR RELAY

OK

5.

CHECK HARNESS AND CONNECTOR (FOG FR RELAY - FOG LIGHT ASSEMBLY)

(a) Disconnect the A43 front fog light assembly LH connector.

(b) Disconnect the A42 front fog light assembly RH connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

5 (FOG FR relay) - A43-2 (B)

Always

Below 1 Ω

5 (FOG FR relay) - A42-2 (B)

Always

Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

6.

CHECK HARNESS AND CONNECTOR (FOG LIGHT ASSEMBLY - BODY GROUND)

(a) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

A43-1 (E) - Body ground

Always

Below 1 Ω

A42-1 (E) - Body ground

Always

Below 1 Ω

OK

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

7.

CHECK HARNESS AND CONNECTOR (POWER SOURCE - FOG FR RELAY)

(a) Remove the FOG FR relay.

(b) Measure the voltage according to the value(s) in the table below.

Standard Voltage:

Tester Connection

Condition

Specified Condition

2 (FOG FR relay) - Body ground

Always

11 to 14 V

5 (FOG FR relay) - Body ground

Always

11 to 14 V

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

8.

INSPECT FOG FR RELAY

HINT:

Click here

NG

REPLACE FOG FR RELAY

OK

9.

CHECK HARNESS AND CONNECTOR (FOG FR RELAY - POWER DISTRIBUTION BOX ASSEMBLY)

(a) Disconnect the 8F power distribution box assembly connector.

(b) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

1 (FOG FR relay) - 8F-25

Always

Below 1 Ω

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

OK

10.

CHECK HARNESS AND CONNECTOR (FOG FR RELAY - FOG LIGHT ASSEMBLY)

(a) Disconnect the A43 front fog light assembly LH connector.

(b) Disconnect the A42 front fog light assembly RH connector.

(c) Measure the resistance according to the value(s) in the table below.

Standard Resistance:

Tester Connection

Condition

Specified Condition

5 (FOG FR relay) - Body ground

Always

10 kΩ or higher

A43-2 (B) - Body ground

Always

10 kΩ or higher

A42-2 (B) - Body ground

Always

10 kΩ or higher

OK

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

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