2003 LEXUS LS430 Diagram AC

Fig. 2: Identifying Intake Air Control System Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
ON-VEHICLE INSPECTION
1.INSPECT INTAKE AIR CONTROL FUNCTION

Fig. 2: System Diagram (W/O Smart Key System)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
COMMUNICATION LINE REFERENCE
SenderReceiverSignalCommunication
Line
Transponder Key
ECUMeter ECUBuzzer Sound SignalBEAN
Driver Door ECUTransponder Key
ECUFront Door Courtesy Switch Signal
(Driver Side)BEAN

Fig. 3: System Diagram (W/ Smart Key System)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
COMMUNICATION LINE REFERENCE
1.FUNCTION OF COMPONENT
SenderReceiverSignalCommunication
Line
Steering Lock
ECUMeter ECUBuzzer Sound SignalBEAN
Driver Door ECUSteering Lock
ECUFront Door Courtesy Switch Signal (Driver
Side)BEAN

to save time. The DATA LIST can be displayed during the ACTIVE TEST.
a. Connect the hand-held tester (with CAN VIM) to the DLC3.
b. Turn the ignition switch ON.
c. Perform the ACTIVE TEST according to the display on the tester.
Meter ECU:
ACTIVE TEST - METER ECU
CIRCUIT DESCRIPTION
This circuit supplies power to operate the driver door ECU.
WIRING DIAGRAM
ItemTest DetailsDiagnostic Note
KEY REMINDER BUZZERCombination meter warning buzzer OFF/ON-

Fig. 14: Wiring Diagram - Driver Door ECU Power Source Circuit
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT FUSE (MPX-IG, AM1, D DOOR, MPX-B1, D/C CUT)
a. Remove the MPX-IG and AM1 fuses from the driver side J/B.
b. Remove the D DOOR and MPX-B1 fuses from the passenger side J/B.
c. Remove the D/C CUT fuse from the FL block assy.
d. Measure the resistance.

CIRCUIT DESCRIPTION
The driver door ECU detects the condition of the front door courtesy lamp switch and sends a switch signal to
the related ECUs via the multiplex communication circuit.
WIRING DIAGRAM
Fig. 17: Wiring Diagram
- Door Courtesy Switch Circuit
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.READ VALUE OF DATA LIST (FRONT DOOR COURTESY LAMP SWITCH)
a. Check the DATA LIST for proper functioning of the door courtesy switch
Multiplex network body ECU (Driver door ECU):

Fig. 2: Lexus Navigation System Diagram (1 Of 2)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Fig. 3: Lexus Navigation System Diagram (2 Of 2)