2003 LEXUS LS430 parking brake

Fig. 17: Identifying VSC Test
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
2. Check that the display changes to "VSC Test" on the multi-information display.
HINT:
"VSC" is displayed while obtaining the zero point. "VSC Test" is displayed when it is
completed.
The zero point calibration is performed only once after the system enters the test mode.
Calibration cannot be performed again until the stored data is cleared once.
f. Turn the ignition switch off.
1.WARNING LIGHT AND INDICATOR LIGHT CHECK
a. Release the parking brake pedal.

1.DIAGNOSIS
FL+ (S42-18) - FL-
(S42-4)P -VFront LH wheel speed
signal inputIG switch ON, slowly turn
left front wheelAC generation
RL+ (S42-20) - RL-
(S42-6)BR-W -
BRRear LH wheel speed signal
inputIG switch ON, slowly turn
left rear wheelAC generation
TS (S42-24) -GND
(S42-1, 32)B - BR,
W-BSensor check inputIG switch ON11 to 14 V
STP (S42-27) -
GND (S42-1, 32)G-W - BR,
W-BStop lamp switch inputStop light switch ON
(Brake pedal pushed)8 to 14 V
STP (S42-27) -
GND (S42-1, 32)G-W - BR,
W-BStop lamp switch inputStop light switch OFF
(Brake pedal released)Below 1.5 V
PKB (S42-28) -
GND (S42-1, 32)B-L - BR,
W-BParking brake switch inputIG switch ON, parking
brake switch ONBelow 1.5 V
PKB (S42-28) -
GND (S42-1, 32)B-L - BR,
W-BParking brake switch inputIG switch ON, parking
brake switch OFF11 to 14 V
BZ (S42-30) -GND
(S42-1, 32)W-R - BR,
W-BBuzzer outputIG switch ON, VSC
buzzer soundsBelow 1.0 <-->
11 to 14 V
BZ (S42-30) -GND
(S42-1, 32)W-R - BR,
W-BBuzzer outputIG switch ON, VSC
buzzer does not sound11 to 14 V
+BS (S42-31) -
GND (S42-1, 32)B - BR,
W-BSolenoid relay power supplyAlways11 to 14 V
FRO (S42-37) -
GND (S42-1, 32)Y-R - BR,
W-BFront RH wheel speed
signal outputVehicle drives at approx.
12 mph (20 km/h)Pulse generation
FLO (S42-38) -
GND (S42-1, 32)Y-B - BR,
W-BFront LH wheel speed
signal outputVehicle drives at approx.
12 mph (20 km/h)Pulse generation
INIT (S42-41) -
GND (S42-1, 32)GR-R -
BR, W-BThe pressure warning
standardization switch InputIG switch ON, The
pressure warning switch
ON
Below 1.5 V
INIT (S42-41) -
GND (S42-1, 32)GR-R -
BR, W-BThe pressure warning
standardization switch InputIG switch ON, The
pressure warning switch
OFF
11 to 14 V
WFSE (S42-42) -
GND (S42-1, 32)LG-B -
BR, W-BWFSE inputIG switch ON11 to 14 V
CSW (S42-43) -
GND (S42-1, 32)Y-G - BR,
W-BTRAC cut switch InputIG switch ON, TRAC
OFF switch is off11 to 14 V
CSW (S42-43) -
GND (S42-1, 32)Y-G - BR,
W-BTRAC cut switch InputIG switch ON, TRAC
OFF switch is onBelow 1.5 V
R+ (S42-45) -GND
(S42-1, 32)R-W - BR,
W-BPower supply for motor
relayIG switch ON11 to 14 V
IG1 (S42-46) -GND
(S42-1, 32)B-R - BR,
W-BIG1 power supplyIG switch ON11 to 14 V

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

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

Fig. 122: Inspecting Parking Brake Switch Assy
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: Go to next step
5.CHECK HARNESS OR CONNECTOR (SKID CONTROL ECU - PARKING BRAKE SWITCH)
a. Disconnect the skid control ECU connector and the parking brake switch 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 CONNECTION SPECIFIED CONDITION
Tester ConnectionSpecified Condition
S42-28 (PKB) - P3-1 (PKB)Below 1 ohms
Tester ConnectionSpecified Condition

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3600580045[-Assy With Nut
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
30.CONNECT BATTERY NEGATIVE TERMINAL
31.ADJUST SHIFT LEVER POSITION (SEE ADJUSTMENT
)
32.INSPECT SHIFT LEVER POSITION (SEE ADJUSTMENT

33.INSPECT PARK/NEUTRAL POSITION SWITCH ASSY (SEE ADJUSTMENT
)
34.INSTALL PROPELLER W/CENTER BEARING SHAFT ASSY (SEE OVERHAUL
)
35.INSTALL EXHAUST PIPE ASSY (SEE REPLACEMENT
)
36.PERFORM INITIALIZATION (SEE INITIALIZATION
)
ADJUSTMENT
1.INSPECT PARK/NEUTRAL POSITION SWITCH ASSY
a. Apply the parking brake and turn the ignition switch to the ON position.
b. Depress the brake pedal and check that the engine starts when the shift lever is set in the N or P
position, but does not start in other positions.
c. Check that the back-up light comes on and the reverse warning buzzer sounds when the shift lever
is set in the R position, but do not function in other positions.

a. Release the parking brake pedal.
b. With the engine running, depress the pedal and measure the pedal reserve distance, as shown in the
illustration.
Pedal reserve distance from asphalt sheet at 490 N (50 kgf, 110.2 lbf): More than 105 mm (4.13 in.)
If incorrect, troubleshoot the brake system.
Fig. 19: Checking Pedal Reserve Distance

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
19.INSTALL FLOOR CARPET ASSY FRONT
20.INSTALL FR DOOR SCUFF PLATE LH (SEE REPLACEMENT
)
21.INSTALL INSTRUMENT PANEL UNDER COVER SUB-ASSY NO.2 (SEE REPLACEMENT
)
22.INSTALL INSTRUMENT PANEL UNDER SAFETY PAD SUB-ASSY NO.1 (SEE
REPLACEMENT
)