DESCRIPTION
If the radio receiver assembly cannot detect the navigation ECU for a certain period of time (90 seconds) after the engine 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.
WIRING DIAGRAM
CAUTION / NOTICE / HINT
NOTICE:
Click here
PROCEDURE
1. | CHECK MAP SCREEN |
(a) Turn the engine switch on (ACC) and wait for 90 seconds.
(b) Press the "MAP" switch and check that the map screen is displayed normally.
Result | Proceed to |
---|---|
Map screen is displayed normally | A |
Map screen is not displayed normally | B |
HINT:
A | USE SIMULATION METHOD TO CHECK |
|
2. | CHECK DTC |
(a) Clear the DTCs.
Body Electrical > Navigation System > Clear DTCs(b) Turn the engine switch off.
(c) Turn the engine switch on (IG) and wait for 90 seconds.
(d) Recheck for DTCs and check that no DTCs are output.
Body Electrical > Navigation System > Trouble CodesOK:
No DTCs are output.
OK | USE SIMULATION METHOD TO CHECK |
|
3. | CHECK HARNESS AND CONNECTOR (NAVIGATION ECU POWER SOURCE) |
(a) Disconnect the J153 navigation ECU connector. |
|
(b) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
J153-23 (GND) - Body ground | Always | Below 1 Ω |
(c) Measure the voltage according to the value(s) in the table below.
Standard Voltage:
Tester Connection | Condition | Specified Condition |
---|---|---|
J153-10 (+B) - Body ground | Always | 11 to 14 V |
NG | REPAIR OR REPLACE HARNESS OR CONNECTOR |
|
4. | CHECK NO. 1 NAVIGATION WIRE (RADIO RECEIVER ASSEMBLY - NAVIGATION ECU) |
(a) Disconnect the z31 radio receiver assembly connector. |
|
(b) Disconnect the z32 navigation ECU connector.
(c) Measure the resistance according to the value(s) in the table below.
Standard Resistance:
Tester Connection | Condition | Specified Condition |
---|---|---|
z31-4 (US4+) - z32-4 (US4+) | Always | Below 1 Ω |
z31-5 (US4-) - z32-5 (US4-) | Always | Below 1 Ω |
z31-6 (UGD4) - z32-6 (UGD4) | Always | Below 1 Ω |
NG | REPLACE NO. 1 NAVIGATION WIRE |
|
5. | REPLACE NAVIGATION ECU |
(a) Replace the navigation ECU with a new or known good one.
Click here
|
6. | CHECK DTC |
(a) Clear the DTCs.
Body Electrical > Navigation System > Clear DTCs(b) Turn the engine switch off.
(c) Turn the engine switch on (IG) and wait for 90 seconds.
(d) Recheck for DTCs and check that no DTCs are output.
Body Electrical > Navigation System > Trouble CodesOK:
No DTCs are output.
OK | END (NAVIGATION ECU IS DEFECTIVE) |
NG | REPLACE RADIO RECEIVER ASSEMBLY |
Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual > Rear Combination Light Assembly (w/o Rear No. 2 Seat): Installation
INSTALLATION CAUTION / NOTICE / HINT HINT:
Use the same procedure for the RH side and LH side.
The following procedure is for the LH side.
PROCEDURE 1. INSTALL REAR COMBINATION LIGHT ASSEMBLY (a) Engage the grommet. (b) Engage the 3 guides and pin to temporarily install the rear combination ...
Lexus RX (RX 350L, RX450h) 2016-2024 Repair Manual > Audio And Visual System (for 12.3 Inch Display): AVC-LAN Circuit
DESCRIPTION Each unit of the audio and visual system connected to the AVC-LAN (communication bus) transmits switch signals via AVC-LAN communication. If a short to +B or short to ground occurs in the AVC-LAN, the audio and visual system will not function normally because communication is not possibl ...