Last Modified: 07-31-2024 6.11:8.1.0 Doc ID: RM1000000025DLT
Model Year Start: 2023 Model: GR Corolla Prod Date Range: [09/2022 - 11/2022]
Title: LIGHTING (EXT): LIGHTING SYSTEM (for TMC Made): Front Fog Light Circuit; 2023 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 - 11/2022]

Front Fog Light Circuit

DESCRIPTION

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

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

  • Inspect the fuses for circuits related to this system before performing the following procedure.
  • Before replacing the main body ECU (multiplex network body ECU), refer to Registration.

    for HV Model:Click here 2023 - 2025 MY Corolla Corolla HV [09/2022 -        ]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, HV Model): REGISTRATION

    for Gasoline Model:Click here 2023 MY Corolla Corolla Hatchback GR Corolla [09/2022 - 11/2022]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function (Gasoline Model, except TMMMS Made)): 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 2023 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [09/2022 -        ]; NETWORKING: CXPI COMMUNICATION SYSTEM: HOW TO PROCEED WITH TROUBLESHOOTING

PROCEDURE

1.

CHECK OPERATION (TAILLIGHTS)

(a) Check the operation of the taillights.

OK:

Taillights operate normally.

NG

GO TO PROBLEM SYMPTOMS TABLE

OK

2.

PERFORM ACTIVE TEST USING GTS

(a) Perform the Active Test according to the display on the GTS.

Body Electrical > Main Body > Active Test

Tester Display

Measurement Item

Control Range

Diagnostic Note

Front Fog Light Relay

Front fog lights

OFF or ON

Light control switch in tail position

Body Electrical > Main Body > Active Test

Tester Display

Front Fog Light Relay

OK:

Front fog light relay operates. (Front fog lights come on.)

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

3.

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

(a) Remove the FR FOG relay.

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

5 (FR FOG relay) - Body ground

Always

11 to 14 V
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

4.

CHECK HARNESS AND CONNECTOR (FR FOG RELAY INPUT VOLTAGE)

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

2 (FR FOG relay) - Body ground

Light control switch in tail or head position

11 to 14 V
NG

GO TO STEP 8

OK

5.

INSPECT FR FOG RELAY

(a) Inspect the FR FOG relay.

Click here 2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 -        ]; LIGHTING (EXT): RELAY: ON-VEHICLE INSPECTION

NG

REPLACE FR FOG RELAY
OK

6.

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

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

(b) Disconnect the A42 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

3 (FR FOG relay) - A43-1 (B)

Always

Below 1 Ω

3 (FR FOG relay) - A42-1 (B)

Always

Below 1 Ω

3 (FR FOG relay) or A43-1 (B) - Body ground

Always

10 kΩ or higher

3 (FR FOG relay) or A42-1 (B) - Body ground

Always

10 kΩ or higher
NG

REPAIR OR REPLACE HARNESS OR CONNECTOR
OK

7.

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

(a) Disconnect the 8H 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 (FR FOG relay) - 8H-7

Always

Below 1 Ω

1 (FR FOG relay) or 8H-7 - Body ground

Always

10 kΩ or higher
OK

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

8.

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

(a) Disconnect the 8H 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 (FR FOG relay) - 8H-7

Always

Below 1 Ω

1 (FR FOG relay) or 8H-7 - Body ground

Always

10 kΩ or higher
OK

REPLACE POWER DISTRIBUTION BOX ASSEMBLY

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR