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
Note
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 Service Bulletin.*1
The vehicle battery supplies power to the main body ECU (multiplex network body ECU) via the door control battery. Therefore, before performing this troubleshooting procedure, make sure to perform an on-vehicle inspection to confirm that the main body ECU (multiplex network body ECU) power source circuit is normal.*2
*1: w/ Smart Entry and Start System
*2: w/ Door Control Battery
PROCEDURE
PERFORM ACTIVE TEST USING GTS
Connect the GTS to the DLC3.
Turn the ignition switch to ON.
Turn the GTS on.
Enter the following menus: Body Electrical / Main Body / Active Test.
Perform the Active Test according to the display on the GTS.
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.
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Tester Display |
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Relay for Interior Light Auto Cut Function |
OK |
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All of the interior lights turn off when ON is selected. |
Result | |||
---|---|---|---|
|
OK |
PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE Click here |
NG |
CHECK HARNESS AND CONNECTOR (POWER SOURCE - INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY)
Disconnect the 3F*1 or 3G*2 instrument panel junction block assembly connector.
Measure the voltage according to the value(s) in the table below.
Standard Voltage | |||||||||
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*1: for LHD
*2: for RHD
Result | |||
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|
NG |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
OK |
INSPECT INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY
*A | for LHD | *B | for RHD |
*a | Component without harness connected (Instrument Panel Junction Block Assembly) |
- | - |
Remove the instrument panel junction block assembly.
Remove the main body ECU (multiplex network body ECU) from the instrument panel junction block assembly.
Measure the voltage according to the value(s) in the table below.
Standard Voltage | |||||||||
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Measure the resistance according to the value(s) in the table below.
Standard Resistance | |||||||||
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Result | |||
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OK |
REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) Click here |
NG |
REPLACE INSTRUMENT PANEL JUNCTION BLOCK ASSEMBLY Click here |