Interior Light Auto Cut Circuit [06/2018 - ]: Procedure

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PERFORM ACTIVE TEST USING TECHSTREAM

Connect the Techstream to the DLC3.
Turn the power switch on (IG).
Turn the Techstream on.
Enter the following menus: Body Electrical / Main Body / Active Test.

Perform the Active Test according to the display on the Techstream.

Body Electrical > Main Body > Active Test

Tester Display	Measurement Item	Control Range	Diagnostic Note
Relay for Interior Light Auto Cut Function	DOME CUT relay	OFF or ON	When performing this Active Test, turn all the interior lights on. OFF: DOME CUT relay on (interior lights turn on) ON: DOME CUT relay off (interior lights turn off)

Body Electrical > Main Body > Active Test

Tester Display
Relay for Interior Light Auto Cut Function

All of the interior lights turn off when ON is selected.

Result

Proceed to
OK
NG

Result:

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE. Refer to PROBLEM SYMPTOMS TABLE [06/2018 - ]

Result:

See step 2

CHECK HARNESS AND CONNECTOR (POWER SOURCE - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)

Disconnect the 3K instrument panel junction block assembly connector.

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

Standard Voltage

Tester Connection	Condition	Specified Condition
3K-1 - Body ground	Power switch off	11 to 14 V

Result

Proceed to
OK
NG

Result:

REPAIR OR REPLACE HARNESS OR CONNECTOR

Result:

See step 3

INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

Component without harness connected
(Instrument Panel Junction Block Assembly)

Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
Refer to REMOVAL [06/2018 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

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

Standard Voltage

Tester Connection	Condition	Specified Condition
3H-19 - Auxiliary battery negative (-)	Auxiliary battery positive (+) → 3K-1 Auxiliary battery negative (-) → MB-23 (DOMR)	11 to 14 V
3D-9 - Auxiliary battery negative (-)	Auxiliary battery positive (+) → 3K-1 Auxiliary battery negative (-) → MB-23 (DOMR)	11 to 14 V
3D-10 - Auxiliary battery negative (-)	Auxiliary battery positive (+) → 3K-1 Auxiliary battery negative (-) → MB-23 (DOMR)	11 to 14 V

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

Standard Resistance

Tester Connection	Condition	Specified Condition
3K-1 - 3H-19	Always	10 kΩ or higher
3K-1 - 3D-9	Always	10 kΩ or higher
3K-1 - 3D-10	Always	10 kΩ or higher

Result

Proceed to
OK
NG

Result:

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU). Refer to REMOVAL [06/2018 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]

Result:

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY. Refer to REMOVAL [06/2018 - 08/2021] , or refer to REMOVAL [08/2021 - 09/2022] , or refer to REMOVAL [09/2022 - ]