brake light LEXUS LS430 2003 Factory User Guide

DTC chart of ABS:
DTC C1232/32, C1234/34, C1243/43,
C1244/44, C1245/45, C1381/97
MALFUNCTION IN DECELERATION/YAW RATE
SENSOR, OPEN OR SHORT IN DECELERATION
SENSOR CIRCUIT, MALFUNCTION IN POWER
SUPPLY VOLTAGE YAW/DECELERATION
SENSOR
DTC C1235/35, C1236/36, C1238/38,
C1239/39
FOREIGN MATTER IS ATTACHED ON TIP OF
RIGHT/LEFT FRONT/REAR SENSOR
DTC C1241/41LOW BATTERY POSITIVE VOLTAGE
DTC C1246/46MALFUNCTION IN MASTER CYLINDER
PRESSURE SENSOR
DTC C1249/49OPEN CIRCUIT IN STOP LIGHT SWITCH CIRCUIT
DTC C1251/51PUMP MOTOR IS LOCKED/OPEN CIRCUIT IN
PUMP MOTOR GROUND
DTC C1267/67Brake Pedal Load Sensing Switch

*2:
1. Keep the vehicle in the stationary condition for 5 seconds or more and depress the brake pedal
lightly 2 or 3 times.
2. Drive the vehicle at the vehicle speed of 31 mph (50 km/h) and keep depressing the brake pedal
strongly for approximately 3 seconds.
3. Repeat the above operation 3 times or more and check that the ABS warning light goes off.
4. Clear the DTC (see DTC CHECK/CLEAR
).
HINT:
In some cases, the hand-held tester cannot be used when ABS warning light remains on.
DTC chart of VSC:
Fig. 43: DTC Information Chart Of VSC

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
HINT:
In some cases, the hand-held tester cannot be used when VSC warning light is always on.

c. Select the DATA LIST mode on the hand-held tester.
MEASUREMENT ITEM / RANGE (DISPLAY) DESCRIPTION
d. Check that the brake fluid pressure value of the master cylinder pressure sensor observed in the
hand held tester changes when the brake pedal is depressed.
OK: Go to next step
When the pedal is depressed, displayed voltage on the hand-held tester increases.
NG: Go to step 2
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
2.INSPECT SKID CONTROL ECU TERMINAL VOLTAGE (STP TERMINAL)
a. Disconnect the skid control ECU connector.
b. Measure the voltage according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
NG: CHECK AND REPLACE STOP LIGHT SWITCH CIRCUIT
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
ItemMeasurement Item / Range (Display)Normal Condition
MAS CYL PRS
1Master cylinder pressure sensor 1 reading /
min.: 0 V, max.: 5 VWhen brake pedal is released:
0.3 to 0.9V
Tester ConnectionSwitch ConditionSpecified Condition
S42-27 (STP) - Body groundBrake pedal depressed8 to 14V
S42-27 (STP) - Body groundBrake pedal releasedBelow 1 V

Fig. 97: Stop Light Switch Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.CHECK STOP LAMP SWITCH OPERATION
a. Check that the stop light comes on when the brake pedal is depressed and turns off when the brake
pedal is released.
OK:

CIRCUIT DESCRIPTION
The BRAKE warning light comes on when the brake fluid is insufficient, the parking brake is applied or the
EBD is defective.
The skid control ECU is connected to the combination meter via CAN and Multiplex communications.
The pad wear indicator is installed to the brake pad (right side).
If the wear indicator wire is open, "Brake Wear" appears on the multi-information display, which indicates that
the pad must be replaced.
WIRING DIAGRAM

Fig. 120: Brake Warning Light Wiring Diagram (1 Of 2)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

Fig. 121: Brake Warning Light Wiring Diagram (2 Of 2)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE
HINT:
When releasing the parking brake, set the chocks to hold the vehicle for safety.
Check that "Brake Wear" does not appear on the multi-information display.
If it appears, check that brake pad thickness and replace the pad as necessary.
1.CHECK BRAKE FLUID LEVEL IN RESERVOIR
a. Check that the brake fluid level is proper.
OK: Go to next step
Brake fluid level is proper.
NG: ADD BRAKE FLUID
OK: Go to next step
2.CHECK DTC
a. Are the DTC recorded for ABS, VSC, CAN and/or Multiplex communication system?
OK: Go to next step
DTC OUTPUT DESCRIPTION
B: REPAIR CIRCUIT INDICATED BY OUTPUT CODE
A: Go to next step
3.INSPECT BRAKE WARNING LIGHT
a. Connect the hand-held tester to the DLC3.
b. Start the engine.
c. Select the item "BRAKE WARN LIGHT" in the ACTIVE TEST and operate the BRAKE warning
light on the hand-held tester.
VEHICLE CONDITION / TEST DETAILS
d. Check that "ON" and "OFF" of the BRAKE warning light are indicated on the combination meter
when usin
g the hand-held tester.
DTC is not outputA
DTC is outputB
ItemVehicle Condition / Test DetailsDiagnostic Note
BRAKE WRN LIGHTTurns BRAKE warning light ON / OFFObserve combination meter

OK: Go to next step
Turn the BRAKE warning light on or off in accordance with the hand-held tester.
NG: Go to step 4
OK: REPLACE ABS & TRACTION ACTUATOR ASSY (SEE REPLACEMENT
)
4.INSPECT PARKING BRAKE SWITCH ASSY
a. Remove the parking brake switch connector.
b. Measure the resistance according to the value (s) in the table below.
Standard:
TESTER CONNECTION SPECIFIED CONDITION
NG: REPLACE PARKING BRAKE SWITCH ASSY
Tester ConnectionSwitch ConditionSpecified Condition
P3-1 - Ground partReleasedBelow 1 ohms
P3-1 - Ground partPushed in1M ohms or higher

HINT:
Confirm the noise conditions and inspect the appropriate noise filter.
First confirm that the foreign noise cannot be heard. Failure to do so will likely result in
misunderstanding the source of the noise.
If more than one source exists, noise should be removed from loudest to quietest.
NG: REINSTALL SPEAKER PROPERLY
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS
TABLE
INSPECTION PROCEDURE
1.CHECK THE CD
a. Check the CD.
OK: The CD is clean.
Noise can be heard when the brake pedal is depressed.Stop light switch
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