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 |
READ NEXT:
Footwell Light Circuit
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:
Diagnostic Trouble Code Chart
DIAGNOSTIC TROUBLE CODE CHART Navigation System DTC No. Detection Item Link B1323 Lost Communication with Haptic Device B1324 Lost Communication with Meter B1325 Lost Communication with HUD B1326 Lost Communication with Clock Device (Local-CAN)
Problem Symptoms Table
PROBLEM SYMPTOMS TABLE HINT:
Use the table below to help determine the cause of problem symptoms. If multiple suspected areas are listed, the potential causes of the symptoms are listed in order of probability in the "Suspected Area" column of the table. Check each symptom by checking the suspect
