Lexus NX: AVC-LAN Circuit
DESCRIPTION
Each audio system component connected to the AVC-LAN (communication bus) transfers switch signals using the audio visual communication local area network.
If a short to +B or short to ground occurs in the AVC-LAN, the audio system will not function normally because communication is not possible.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
When replacing the radio receiver assembly, always replace it with a new one.
If a radio receiver assembly which was installed to another vehicle is used, the following may occur:
- A communication malfunction DTC may be stored.
- The radio receiver assembly may not operate normally.
HINT:
Depending on the parts that are replaced during vehicle inspection or maintenance, performing initialization, registration or calibration may be needed. Refer to Precaution for Navigation System.
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PROCEDURE
| 1. | INSPECT RADIO RECEIVER ASSEMBLY |
(a) Remove the radio receiver assembly.
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| (b) Measure the resistance according to the value(s) in the table below. Standard Resistance:
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| NG | .gif) | REPLACE RADIO RECEIVER ASSEMBLY |
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| 2. | CHECK HARNESS AND CONNECTOR (AVC-LAN CIRCUIT) |
(a) Disconnect the I151 radio receiver assembly connector.
(b) Disconnect the I42 multi-display assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
| Tester Connection | Condition | Specified Condition |
|---|---|---|
| I151-5 (TX1+) - I42-7 (TX+) | Always | Below 1 Ω |
| I151-6 (TX1-) - I42-19 (TX-) | Always | Below 1 Ω |
| I151-5 (TX1+) - Body ground | Always | 10 kΩ or higher |
| I151-6 (TX1-) - Body ground | Always | 10 kΩ or higher |
| NG | | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
| 3. | INSPECT MALFUNCTIONING PARTS |
(a) Disconnect and reconnect each slave unit one by one until the master unit returns to normal operation.
HINT:
- Check all slave units.
- When disconnecting a slave unit causes the master unit to return to normal operation, this indicates that the slave unit is malfunctioning. Replace the malfunctioning slave unit.
OK:
Master unit returns to normal operation.
| OK | | REPLACE MALFUNCTIONING PARTS |
| NG | | REPLACE RADIO RECEIVER ASSEMBLY |
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SEE MORE:
Precaution
PRECAUTION TROUBLESHOOTING PRECAUTIONS (a) When there is a malfunction with terminal contact points or a problem with the installation of a part, reconnecting the connectors or removal/installation of the suspected parts may return the system to the normal condition either completely or temporarily.
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