Last Modified: 05-13-2024 6.11:8.1.0 Doc ID: RM100000001GTRQ
Model Year Start: 2020 Model: GR Corolla Prod Date Range: [01/2019 -           ]
Title: LIGHTING (EXT): AUTOMATIC LIGHT CONTROL SENSOR: ON-VEHICLE INSPECTION; 2020 - 2025 MY Corolla Corolla Hatchback Corolla HV GR Corolla [01/2019 -        ]

ON-VEHICLE INSPECTION

PROCEDURE

1. INSPECT AUTOMATIC LIGHT CONTROL SENSOR

(a) Disconnect the h1 automatic light control sensor connector.

*a

Front view of wire harness connector

(to Automatic Light Control Sensor)

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

Standard Voltage:

Tester Connection

Condition

Specified Condition

*1: for HV Model

*2: for Gasoline Model

h1-1 (CLTB) - h1-2 (CLTE)

Power switch off*1

Below 1 V

Engine switch off*2

Power switch on (IG)*1

11 to 14 V

Engine switch on (IG)*2

Standard Resistance:

Tester Connection

Condition

Specified Condition

h1-2 (CLTE) - Body ground

Always

Below 1 Ω

If the result is not as specified, there may be a malfunction on the wire harness side.

(c) Connect the h1 automatic light control sensor connector.

(d) Connect an oscilloscope to terminals h1-2 (CLTE) and h1-4 (CLTS) of the automatic light control sensor connector and check the waveform.

*a

Component with harness connected

(Automatic Light Control Sensor)

*b

Waveform

OK:

Tester Connection

Condition

Tool Setting

Specified Condition

*1: for HV Model

*2: for Gasoline Model

h1-2 (CLTE) - h1-4 (CLTS)

Power switch on (IG)*1

2 V/DIV., 10 ms./DIV.

Pulse generation

(See waveform)

Engine switch on (IG)*2

HINT:

The communication waveform changes according to the surrounding brightness.

If the result is not as specified, the automatic light control sensor may be malfunctioning.