Lexus NX: Interior Light Switch Signal Circuit
DESCRIPTION
The main body ECU (multiplex network body ECU) detects the condition of the door switch and front dome light switch.
WIRING DIAGRAM
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CAUTION / NOTICE / HINT
NOTICE:
- Recognition code registration is necessary when replacing the main body ECU (multiplex network body ECU).
- If the main body ECU (multiplex network body ECU) is replaced, refer to Registration.
PROCEDURE
| 1. | READ VALUE USING TECHSTREAM (DOME LIGHT DOOR SW, DOME LIGHT SW) |
(a) Using the Techstream, read the Data List.
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| Tester Display | Measurement Item | Range | Normal Condition | Diagnostic Note |
|---|---|---|---|---|
| Dome Light DOOR SW | Door switch signal | ON or OFF | ON: Door switch on OFF: Door switch off | - |
| Dome Light SW | Front dome light switch signal | ON or OFF | ON: Front dome light switch on OFF: Front dome light switch off | - |
| Tester Display |
|---|
| Dome Light DOOR SW |
| Dome Light SW |
OK:
Normal conditions listed above are displayed.
| OK | .gif) | PROCEED TO NEXT SUSPECTED AREA SHOWN IN PROBLEM SYMPTOMS TABLE |
|
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| 2. | INSPECT MAP LIGHT ASSEMBLY |
(a) Remove the map light assembly.
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(b) Inspect the map light assembly.
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| NG | | REPLACE MAP LIGHT ASSEMBLY |
|
| 3. | CHECK HARNESS AND CONNECTOR (MAP LIGHT ASSEMBLY - MAIN BODY ECU) |
(a) Disconnect the T6 and T7 map light assembly connectors.
(b) Disconnect the I47 main body ECU (multiplex network body ECU) connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| T7-18 (DOOR) - I47-27 (DMDR) | Always | Below 1 Ω |
| T7-19 (CILL) - I47-28 (DMON) | Always | Below 1 Ω |
| T7-20 (GND9) - Body ground | Always | 10 kΩ or higher |
| T7-18 (DOOR) or I47-27 (DMDR) - Body ground | Always | 10 kΩ or higher |
| T7-19 (CILL) or I47-28 (DMON) - Body ground | Always | 10 kΩ or higher |
| OK | | REPLACE MAIN BODY ECU (MULTIPLEX NETWORK BODY ECU) |
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
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DESCRIPTION The main body ECU (multiplex network body ECU) controls the operation of the following lights:
No. 1 interior illumination light assembly LH
No. 1 interior illumination light assembly
Power Switch Illumination Circuit
DESCRIPTION The illuminated entry system controls the power switch illumination. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE:
Recognition code registration is necessary when replacing the main b
Door Unlock Detection Switch Circuit
DESCRIPTION The main body ECU (multiplex network body ECU) detects the condition of each door unlock detection switch. WIRING DIAGRAM CAUTION / NOTICE / HINT NOTICE:
Recognition code registration
SEE MORE:
Installation
INSTALLATION PROCEDURE 1. INSTALL STOP LIGHT CONTROL ECU ASSEMBLY (a) Attach the clamp to install the stop light control ECU assembly. (b) Connect the connector. 2. INSTALL LOWER NO. 1 INSTRUMENT PANEL FINISH PANEL Click here 3. INSTALL NO. 1 INSTRUMENT PANEL UNDER COVER SUB-ASSEMBLY Click here
Installation
INSTALLATION CAUTION / NOTICE / HINT NOTICE: While the battery is connected, even if the power switch is off, the brake control system activates when the brake pedal is depressed or any door courtesy switch is turned on. Therefore, when servicing the brake system components, do not depress the brake
