Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000001GL90
Model Year Start: 2020 Model: GR Corolla Prod Date Range: [01/2019 - 03/2019]
Title: LIGHTING (EXT): LIGHTING SYSTEM (for Gasoline Model without AFS): Headlight Dimmer Switch Circuit; 2020 MY Corolla Corolla Hatchback GR Corolla [01/2019 - 03/2019]

Headlight Dimmer Switch Circuit

DESCRIPTION

The steering sensor receives the following switch information:

  • Light control switch in DRL OFF*1, off*2, tail, head or AUTO position
  • Dimmer switch in high, low or high flash (pass) position
  • Fog light switch*3 in front or off position
    • *1: w/ DRL OFF Switch
    • *2: w/o DRL OFF Switch
    • *3: w/ Front Fog Light

WIRING DIAGRAM

CAUTION / NOTICE / HINT

NOTICE:

Before replacing the main body ECU (multiplex network body ECU), refer to Registration.*

Click here 2020 MY Corolla Corolla Hatchback GR Corolla [01/2019 - 09/2019]; THEFT DETERRENT / KEYLESS ENTRY: SMART KEY SYSTEM (for Start Function, Gasoline Model): REGISTRATION

  • *: w/ Smart Key System

PROCEDURE

1.

READ VALUE USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Chassis / Steering Angle Sensor / Data List.

(e) Read the Data List according to the display on the Techstream.

Chassis > Steering Angle Sensor > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Light OFF Switch

Light control switch DRL OFF*1 or off*2 position signal

OFF or ON

OFF: Light control switch not in DRL OFF*1 or off*2 position

ON: Light control switch in DRL OFF*1 or off*2 position

-

Auto Light Switch

Light control switch AUTO position signal

OFF or ON

OFF: Light control switch not in AUTO position

ON: Light control switch in AUTO position

-

Head Light Switch (Tail)

Light control switch tail position signal

OFF or ON

OFF: Light control switch in neither tail nor head position

ON: Light control switch in tail or head position

-

Head Light Switch (Head)

Light control switch head position signal

OFF or ON

OFF: Light control switch not in head position

ON: Light control switch in head position

-

High Beam Main Switch

Dimmer switch high position signal

OFF or ON

OFF: Dimmer switch not in high position

ON: Dimmer switch in high position

-

Passing Light Switch

Dimmer switch high flash position (pass) signal

OFF or ON

OFF: Dimmer switch not in high flash position

ON: Dimmer switch in high flash position

-

Front Fog Light Switch

Front fog light switch signal

OFF or ON

OFF: Front fog light switch off

ON: Front fog light switch on

w/ Front Fog Light

  • *1: w/ DRL OFF Switch
  • *2: w/o DRL OFF Switch

Chassis > Steering Angle Sensor > Data List

Tester Display

Light OFF Switch

Auto Light Switch

Head Light Switch (Tail)

Head Light Switch (Head)

High Beam Main Switch

Passing Light Switch

Front Fog Light Switch

OK:

Normal conditions listed above are displayed.

NG

GO TO STEP 5

OK

2.

READ VALUE USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(c) Turn the Techstream on.

(d) Enter the following menus: Body Electrical / Main Body / Data List.

(e) Read the Data List according to the display on the Techstream.

Body Electrical > Main Body > Data List

Tester Display

Measurement Item

Range

Normal Condition

Diagnostic Note

Head Light SW (Head)

Light control switch head position signal

OFF or ON

OFF: Light control switch not in head position

ON: Light control switch in head position

-

Body Electrical > Main Body > Data List

Tester Display

Head Light SW (Head)

OK:

Normal conditions listed above are displayed.

OK

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

NG

3.

INSPECT STEERING SENSOR

*a

Component without harness connected

(Steering Sensor)

-

-

(a) Remove the steering sensor.

Click here 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; BRAKE CONTROL / DYNAMIC CONTROL SYSTEMS: STEERING ANGLE SENSOR: REMOVAL

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

I46-7 (HEAD) - z17-4 (H)

Always

Below 1 Ω

NG

REPLACE STEERING SENSOR

OK

4.

CHECK HARNESS AND CONNECTOR (STEERING SENSOR - MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU))

(a) Disconnect the I85 main body ECU (multiplex network body ECU) connector.

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

Standard Resistance:

Tester Connection

Condition

Specified Condition

I46-7 (HEAD) - I85-16 (HEAD)

Always

Below 1 Ω

I46-7 (HEAD) or I85-16 (HEAD) - Body ground

Always

10 kΩ or higher

OK

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

NG

REPAIR OR REPLACE HARNESS OR CONNECTOR

5.

INSPECT TURN SIGNAL SWITCH

(a) Remove the turn signal switch.

Click here 2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 -        ]; LIGHTING (EXT): HEADLIGHT DIMMER SWITCH: REMOVAL

(b) Inspect the turn signal switch.

Click here 2019 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [06/2018 -        ]; LIGHTING (EXT): HEADLIGHT DIMMER SWITCH: INSPECTION

NG

REPLACE TURN SIGNAL SWITCH

OK

6.

INSPECT STEERING WHEEL SWITCH HOUSING

(a) Remove the steering wheel switch housing.

Click here 2020 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 - 03/2019]; LIGHTING (EXT): SWITCH HOUSING: REMOVAL

(b) Inspect the steering wheel switch housing.

Click here 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 -        ]; LIGHTING (EXT): SWITCH HOUSING: INSPECTION

OK

REPLACE STEERING SENSOR

NG

REPLACE STEERING WHEEL SWITCH HOUSING