2003 LEXUS LS430 Identifying ac

Fig. 90: Identifying ABS-IG Fuse Location
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: INSPECT FOR SHORT CIRCUIT IN ALL HARNESS AND COMPONENTS CONNECTED
TO ECU-IG FUSE

TESTER CONNECTION SPECIFIED CONDITION
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR (GND TERMINAL - BODY
GROUND)
Fig. 92: Identifying Skid Control ECU Connector Terminals

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: CHECK AND REPAIR HARNESS AND CONNECTOR (IG1 TERMINAL - BATTERY)
CIRCUIT DESCRIPTION
Master c
ylinder pressure sensor is connected to the skid control ECU in the actuator.
Tester ConnectionSpecified Condition
S42-32 (GND) - Body groundBelow 1ohms

Fig. 95: Identifying Skid Control ECU Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
CIRCUIT DESCRIPTION
Recognition of brake operation by sending stop lamp signal to skid control ECU.
Fig. 96: DTC C1249/49 Detecting Condition And Trouble Area

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

Fig. 99: Identifying Driver Side J/B ECU connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go to next step
4.CHECK HARNESS AND CONNECTOR (STPA OF DRIVER SIDE J/B ECU - STP OF SKID
CONTROL ECU)
a. Disconnect driver side J/B ECU connector and skid control ECU connector.

Fig. 100: Identifying Driver Side J/B ECU Connector And Skid Control ECU Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTO
R

Fig. 101: Identifying Stop Lamp Switch Assy Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPLACE STOP LAMP SWITCH ASSY
OK: Go to next step
7.CHECK HARNESS AND CONNECTOR (STOP LAMP SWITCH - DRIVER SIDE J/B ECU)
a. Disconnect the stop lamp switch connector and driver side J/B connector.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
c. Measure the resistance according to the value (s) in the table below.
Standard:
Tester ConnectionSpecified Condition
(S19-1) - D3-13 (STP-1)Below 1 ohms

Fig. 102: Identifying Stop Lamp Switch Connector And Driver Side J/B Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: Go to next step
8.CHECK HARNESS AND CONNECTOR (STPA OF DRIVER SIDE J/B ECU - STP OF SKID
CONTROL ECU)
a. Disconnect the driver side J/B connector and skid control ECU connector.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
Standard:
TESTER CONNECTION SPECIFIED CONDITION
Tester ConnectionSpecified Condition
D5-3 (STPA) - S42-27 (STP)Below 1 ohms
Tester ConnectionSpecified Condition
S42-27 (STP) - Body ground1 Mohms or higher

Fig. 103: Identifying Driver Side J/B Connector And Skid Control ECU Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR