AVC-LAN Circuit
Each unit of the navigation system connected to the AVC-LAN (communication bus) transfers the switch signals using the AVC-LAN.
If a short to +B or short to ground occurs in the AVC-LAN, the navigation system will not function normally because communication is not possible.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
HINT:
The navigation receiver assembly is the master unit.
PROCEDUREINSPECT NAVIGATION RECEIVER ASSEMBLY
(a) Disconnect the navigation receiver assembly connectors.
(b) Measure the resistance according to the value(s) in the table below. Standard Resistance:
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| NG | ![]() |
REPLACE NAVIGATION RECEIVER ASSEMBLY |
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CHECK HARNESS AND CONNECTOR (AVC-LAN CIRCUIT)
(a) Disconnect the N25 navigation receiver assembly connector.
(b) Disconnect the S23 stereo component amplifier assembly connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
|---|---|---|
N25-7 (TX1+) - S23-8 (TX+) |
Always |
Below 1 Ω |
N25-8 (TX1-) - S23-7 (TX-) |
Always |
Below 1 Ω |
N25-7 (TX1+) - Body ground |
Always |
10 kΩ or higher |
N25-8 (TX1-) - Body ground |
Always |
10 kΩ or higher |
| NG | ![]() |
REPAIR OR REPLACE HARNESS OR CONNECTOR |
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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.
- If disconnecting a slave unit causes the master unit to return to normal operation, the slave unit is defective and should be replaced.
OK:
Master unit returns to normal operation.
| OK | ![]() |
REPLACE MALFUNCTIONING PARTS |
| NG | ![]() |
REPLACE NAVIGATION RECEIVER ASSEMBLY |
Test yourself
A quick Toyota Tacoma quiz: every answer comes with an explanation and a link to the manual page.

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