fuse diagram LEXUS LS430 2003 Factory Repair Manual

Fig. 71: ABS Solenoid Relay Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT FUSE (ABS1 FUSE)
a. Remove the ABS 1 fuse from the fusible link block.
b. Measure the resistance according to the value (s) in the table below.
Standard:
ABS 1 FUSE DESCRIPTION
ABS 1 fuseBelow 1 ohms (Continuity)

Fig. 89: Low Battery Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT FUSE (ABS-IG FUSE)
a. Remove the ABS-IG Fuse from the driver side J/B.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
Tester ConnectionSpecified Condition
ABS-IG fuseBelow 1 ohms (Continuity)

NG: REPAIR OR REPLACE AIR DUCT
OK: REPLACE SEAT CLIMATE CONTROL CONTROLLER (SEATBACK OR SEAT
CUSHION)
CIRCUIT DESCRIPTION
If the climate control seat does not operate, the seat climate control blower (climate control ECU) or the wire
harness may be malfunctioning.
WIRE DIAGRAM
Fig. 51: Climate Control System Does Not Operate On Driver Side
- Wire Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT FUSE (D S/HTR)
a. Remove the D S/HTR fuse from the driver side J/B.
b. Measure the resistance of the fuse.
Standard: Below 1 ohms
NG: REPLACE FUSE
OK: Go to next step
2.CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL
ECU) - BATTERY)
a. Disconnect the C20 blower connector.

CIRCUIT DESCRIPTION
If the climate control seat does not operate, the seat climate control blower (climate control ECU) or the wire
harness may be malfunctioning.
WIRE DIAGRAM
Fig. 58: Climate Control System Does Not Operate On Passenger Side
- Wire Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT FUSE (P S/HTR)
a. Remove the P S/HTR fuse from the driver side J/B.
b. Measure the resistance of the relay.
Standard: Below 1 ohms
NG: REPLACE FUSE
OK: Go to next step
2.CHECK WIRE HARNESS (SEAT CLIMATE CONTROL BLOWER (CLIMATE CONTROL
ECU) - BATTERY)
a. Disconnect the C21 blower connector.
b. Measure the voltage of the wire harness side connector.
Standard:
TESTER CONNECTION AND SPECIFIED CONDITION
Tester ConnectionConditionSpecified Condition

Fig. 18: DTC P0500 And P0503 Problem Symptom Diagnostic Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM
See WIRING DIAGRAM

INSPECTION PROCEDURE
See INSPECTION PROCEDURE
.
CIRCUIT DESCRIPTION
When the brake pedal is depressed, the stop lamp switch assy sends a signal to the ECM. When the ECM
receives this signal, it cancels the cruise control.
Fail-safe function operates to enable normal driving even if there is a malfunction in the stop lamp signal
circuit.
The cancel condition occurs when positive battery voltage is applied to terminal STP.
When the brake is applied, battery positive voltage is normally applied to terminal STP of the ECM through the
STOP fuse and the stop lamp switch assy, and the ECM turns the cruise control off.
Fig. 19: DTC P0571 Problem Symptom Diagnostic Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM

Fig. 8: Rear Window Defogger System - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT FUSE
a. Select the ACTIVE TEST, use the han
d-held tester to generate a control command, and then check

Fig. 42: Driver Door ECU Power Source Circuit - Wiring Diagram
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.
Standard: Below 1 ohms

Fig. 48: Rear Door LH ECU Power Source Circuit - Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT FUSE (MPX-IG, AM1, RR DOOR LH, MPX-B1, D/C CUT)
a. Remove the MPX-IG and AM1 fuses from the driver side J/B.

Fig. 51: Rear Door RH ECU Power Source Circuit -Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.INSPECT FUSE (MPX-IG, AM1, RR DOOR RH, MPX-B1, D/C CUT)
a. Remove the MPX-IG and AM1 fuses from the driver side J/B.
b. Remove the MPX-B1 and RR DOOR RH fuses from the passenger side J/B.
c. Remove the D/C CUT fuse from the FL block assy.
d. Measure the resistance.
Standard: Below 1 ohms
NG: REPLACE FUSE
OK: Go to Next Step.
2.INSPECT RELAY (Marking: D-IG1)
a. Remove the D-IG1 relay from the driver side J/B.
b. Measure the resistance.
Fig. 52: Inspecting Relay (D
-IG1)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

CIRCUIT DESCRIPTION
See CIRCUIT DESCRIPTION
.
Fig. 42: DTC P0500 And P0503 Problem Symptom Diagnostic Chart

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
WIRING DIAGRAM
See WIRING DIAGRAM
.
INSPECTION PROCEDURE
See INSPECTION PROCEDURE
.
CIRCUIT DESCRIPTION
When the brake pedal is depressed, the stop lamp switch assy sends a signal to the ECM. When the ECM
receives this signal, it cancels the cruise control.
The fail-safe function operates to enable normal driving even if there is a malfunction in the stop lamp signal
circuit.
The cancel condition occurs when positive battery voltage is applied to terminal STP.
When the brake is applied, battery positive voltage is normally applied to terminal STP of the ECM through the
STOP fuse and the stop lamp switch ass
y, and the ECM turns the cruise control off.