Toyota CH-R Service Manual: Interior Light Auto Cut Circuit

Toyota CH-R Service Manual / Lighting (int) / Lighting System / Interior Light Auto Cut Circuit

DESCRIPTION

The main body ECU (multiplex network body ECU) controls operation of the DOME CUT relay in order to supply power to the interior lights. When the battery saving function operates while the interior lights are on, the main body ECU (multiplex network body ECU) opens the DOME CUT relay to turn off the 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*1.
Click here
- *1: w/ Smart Key System

PROCEDURE

1.	PERFORM ACTIVE TEST USING TECHSTREAM

(a) Connect the Techstream to the DLC3.

(b) Turn the ignition switch to ON.

(d) Enter the following menus: Body Electrical / Main Body / Active Test.

(e) 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	ON or OFF	When performing this active test, turn all the interior lights on. ON: DOME CUT relay off (interior lights turn off) OFF: DOME CUT relay on (interior lights turn on)

Body Electrical > Main Body > Active Test

Tester Display
Relay for Interior Light Auto Cut Function

OK:

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

PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE

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

(a) Disconnect the 3K instrument panel junction block assembly connector.

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

Standard Voltage:

Tester Connection	Condition	Specified Condition
3K-1 - Body ground	Always	11 to 14 V

REPAIR OR REPLACE HARNESS OR CONNECTOR

3.	INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

(a) Remove the instrument panel junction block assembly.

Click here

(b) Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.

Click here

Component without harness connected

(Instrument Panel Junction Block Assembly)

Standard Voltage:

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

Tester Connection

Condition

Specified Condition

3H-19 - Battery negative terminal

Battery positive (+) → 3K-1

Battery negative (-) → MB-23 (DOMR)

11 to 14 V

3D-9 - Battery negative terminal

Battery positive (+) → 3K-1

Battery negative (-) → MB-23 (DOMR)

11 to 14 V

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

REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU)

REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY

Interior Light Circuit

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Toyota CH-R Service Manual: Interior Light Auto Cut Circuit

Interior Light Circuit

Ambient Illumination Light Circuit

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