DTC B1543: Extension Module Disconnected 2 [06/2018 - 09/2022]: Description
WARNING: This page is about a different car, the 2022 Lexus ES 300h, 2021 Lexus ES 300h, 2020 Lexus ES 300h, and 2019 Lexus ES 300h. However, it is still accessible from the selected car via links, so may be relevant.
If the radio receiver assembly cannot detect the navigation ECU for a certain period of time (90 seconds) after the power switch is turned on (ACC) and the radio receiver assembly confirms that the information is missing by checking past navigation ECU recognition information (registered information), this DTC will be stored.
HINT:
The Navigation system uses USB communication between devices. If an open, short, short to +B or short to ground occurs in the USB circuit, communication is interrupted and the Navigation system will not operate normally.
| DTC No. | Detection Item | DTC Detection Condition | Trouble Area |
|---|---|---|---|
| B1543 | Extension Module Disconnected 2 | Navigation ECU disconnected |
|
HINT:
This DTC may be stored due to environmental reasons such as electrical noise or interference.