sensor LEXUS LS430 2003 Factory Repair Manual

bumper reinforcement can be removed in step (9).
Fig. 6: Removing Radiator Support Reinforcement Lower

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
9.REMOVE FRONT BUMPER REINFORCEMENT SUB-ASSY
a. Remove the 6 bolts and reinforcement.
10.REMOVE LASER SENSOR (W/ RADAR CRUISE)
11.REMOVE FOG LAMP ASSY LH
a. Using a screwdriver, disengage the 2 claws and remove the fog lamp.
HINT:
Tape the screwdriver tip before use.

Fig. 8: Removing Headlamp Cleaner Washer Nozzle (W/Headlamp Cleaner)
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
14.REMOVE HEADLAMP WASHER ACTUATOR SUB-ASSY LH (W/ HEADLAMP CLEANER)
a. Remove the screw and actuator.
15.REMOVE HEADLAMP WASHER ACTUATOR SUB-ASSY RH (W/ HEADLAMP CLEANER)
a. Remove the screw and actuator.
16.REMOVE ULTRASONIC SENSOR NO. 1 (w/ CLEARANCE SONAR SYSTEM)
a. Using a screwdriver, remove the retainer and sensor.
HINT:
Tape the screwdriver tip before use.
17.REMOVE FRONT BUMPER EXTENSION MOUNTING BRACKET
a. Remove the 2 screws and mounting bracket.
18.REMOVE FRONT BUMPER SIDE RETAINER LH
a. Use a drill that has a tip of less than phis 4 mm (0.16 in.).
b. Tape the drill tip as shown in Fig. 9.

11.REMOVE QUARTER PANEL MUDGUARD SUB-ASSY REAR RH (W/ MUDGUARD)
a. Remove the 4 screws and mudguard.
12.REMOVE REAR BUMPER COVER
a. Using a screwdriver, remove the 4 clips.
HINT:
Tape the screwdriver tip before use.
Fig. 15: Removing Rear Bumper Cover Clips

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
b. Remove the 8 nuts.
c. Remove the 2 bolts and 2 screws.
d. Using a screwdriver, disengage the 2 clips labeled A and 2 clips labeled B. Then remove the
bumper cover.
e. w/ Clearance sonar system:
Disconnect the 4 sensor connectors.

20.REMOVE REAR BUMPER SIDE MOUNTING BRACKET LH
a. Remove the screw and bracket.
21.REMOVE REAR BUMPER SIDE MOUNTING BRACKET RH
a. Remove the screw and bracket.
22.REMOVE REAR BUMPER ARM SUPPORT REINFORCE SUB-ASSY LH
a. Remove the 2 bolts, nut and arm support.
23.REMOVE REAR BUMPER ARM SUPPORT REINFORCE SUB-ASSY RH
a. Remove the 2 bolts, nut and arm support.
24.REMOVE REAR BUMPER RETAINER LOWER LH
a. Remove the 3 screws and retainer lower.
25.REMOVE REAR BUMPER RETAINER LOWER RH
a. Remove the 3 screws and retainer lower.
26.REMOVE ULTRASONIC SENSOR NO. 1 (w/ CLEARANCE SONAR SYSTEM)
a. Remove the 4 retainers and 4 sensors.
27.REMOVE REAR BUMPER molding
HINT:
Remove the double-sided tape completely from the bumper. Double-sided tape interferes with the
installation of the molding to the bumper.
28.REMOVE REAR BUMPER SIDE RETAINER NO. 3 LH
a. Remove the 2 clips and side retainer.
29.REMOVE REAR BUMPER SIDE RETAINER NO. 3 RH
a. Remove the 2 clips and side retainer.
30.INSTALL REAR BUMPER ARM SUPPORT REINFORCE SUB-ASSY LH
a. Install the arm support with the 2 bolts and nut.
Torque: 20 N.m (200 kgf.cm, 15 ft.lbf)
31.INSTALL REAR BUMPER ARM SUPPORT REINFORCE SUB-ASSY RH
a. Install the arm support with the 2 bolts and nut.
Torque: 20 N.m (200 kgf.cm, 15 ft.lbf)
32.INSTALL REAR BUMPER REINFORCEMENT SUB-ASSY
a. Install the reinforcement with the 2 bolts and nut.
Torque: 20 N.m (200 kgf.cm, 15 ft.lbf)
33.INSTALL REAR BUMPER SIDE RETAINER LH
a. Using an air riveter or hand riveter with nose piece, strike waterproof rivets of phis 4.9 mm (0.19
in.) into the side retainer to install the rivet to the bumper cover.

3.SYSTEM OPERATION
The front power seat's adjustment and position memory are shown in the chart below.
SYSTEM OPERATION
For the memory function, first, memory switch operation is transferred from the driver door ECU to the
driver seat ECU via the multiplex communication line. Then, either the seat position is recorded in
memory or a previously recorded seat position is recalled.
HINT:
Use this procedure to troubleshoot the front power seat control system with memory function.
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030018001100030003[
1.VEHICLE BROUGHT TO WORKSHOP
2.CUSTOMER PROBLEM ANALYSIS CHECK AND PROBLEM SYMPTOM CHECK (SEE
CUSTOMER PROBLEM ANALYSIS CHECK
)
3.CHECK COMMUNICATION FUNCTION OF LARGE-SCALE MULTIPLEX
COMMUNICATION SYSTEM (BEAN)
seat headrest raises and lowers.
Seat position sensorIs built in each seat adjuster and sends seat position data to driver seat
ECU so that it can detect seat positions at all times.
Seat control switchBased on switches operated, seat adjuster signals are input into driver seat
ECU and seat is adjusted accordingly. Lumbar support adjustments are
also done.
Set switch Memory switchWhen set switch and memory switch are pressed simultaneously, SET, 1, 2
or 3 switch is input to driver door ECU and driver side's seat position is
recorded. Then, when memory switch is pressed, SET, 1, 2 or 3 switch is
input to driver door ECU and driver side's seat position changes according
to memory.
Seat Adjustment FunctionDriverFront Passenger
Fore-and-Aft SlidePower and memoryPower
RecliningPower and memoryPower
Cushion SlidePower and memory-
Front Vertical HeightPower and memoryPower
Rear VerticalPower and memoryPower
Dual Lumbar SupportPower-
Single Lumbar Support-Manual
Headrest Fore-and-AftManualManual
Headrest HeightPower and memoryPower

Fig. 22: Identifying D27 Driver Seat ECU Connector Terminals And Power Seat Motor Connector
Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE WIRE HARNESS AND CONNECTOR
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS
TABLE
CIRCUIT DESCRIPTION
The position sensor detects seat movement and sends pulse signals to the driver seat ECU for use with the
memory function.
The ECU records the number of pulses relative to a previously recorded seat position and uses this data to
return the seat to that position.
If a malfunction occurs in a position sensor and seat movement does not result in pulse signals being input into
the ECU, the memory function is deactivated.
WIRING DIAGRAM

Fig. 23: Position Sensor Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

INSPECTION PROCEDURE
1.READ VALUE OF HAND-HELD TESTER
a. Connect the hand-held tester (with CAN VIM) to the DLC3.
b. Turn the ignition switch ON and press the hand-held tester main switch ON.
c. Select the items below in the DATA LIST, and read the hand-held tester's screen.
d. Watch the hand-held tester screen while adjusting the seat with the power seat control switches.
Check that the position sensor value changes.
e. Watch the hand-held tester screen while adjusting the seat with the power seat control switches.
Check that the motor status changes from STANDBY to MOVING.
HINT:
When the seat is at an extreme position (for example, seatback position fully forward or sliding position
fully rearward) and the power seat control switch is held down, the motor status should read LOCK.
When the switch is released, the motor status should change to STANDBY.
Driver seat ECU:
Fig. 24: Driver Seat ECU
- Data List Chart
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK:
Position sensor values should vary within the minimum and maximum values shown in the chart
above.
For the tester's motor status item, the display should change between STANDBY, MOVING and

LOCK according to the chart above.
NG: Go to step 2
OK: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN ON PROBLEM SYMPTOMS
TABLE
2.CHECK WIRE HARNESS (DRIVER SEAT ECU - POWER SEAT SENSOR AND BODY
GROUND)
a. Disconnect the D27 and D28 ECU connectors.
b. Disconnect the P40, P41, P42, P43, P44 and P45 sensor connectors.
c. Measure the resistance of the wire harness side connectors.
Standard:
TESTER CONNECTION AND SPECIFIED CONDITION
Tester connectionSpecified condition
D27-12 (H+) - P40-1 (UP)Below 1 ohms
D27-3 (H-) - P40-5 (DOWN)Below 1 ohms
D28-7(SSRH) - P40-4(O/P)Below 1 ohms
D28-16 (PVCC) - P40-2 (VCC)Below 1 ohms
D28-16 (PVCC) - P44-3 (VCC)Below 1 ohms
D28-13 (SSRR) - P44-1 (O/P)Below 1 ohms
D28-16 (PVCC) - P43-3 (VCC)Below 1 ohms
D28-6 (SSRV) - P43-1 (O/P)Below 1 ohms
D28-16 (PVCC) - P45-3 (VCC)Below 1 ohms
D28-5 (SSRS) -P45-1 (O/P)Below 1 ohms
D28-16 (PVCC) - P41-3 (VCC)Below 1 ohms
D28-15 (SSRC) - P41-1 (O/P)Below 1 ohms
D28-16 (PVCC) - P42-3 (VCC)Below 1 ohms
D28-14 (SSFV) - P42-1 (O/P)Below 1 ohms
D28-1 (SGND) - Body groundBelow 1 ohms
P40-3 (GND) - Body groundBelow 1 ohms
P44-2 (GND) - Body groundBelow 1 ohms
P43-2 (GND) - Body groundBelow 1 ohms
P45-2 (GND) - Body groundBelow 1 ohms
P41-2 (GND) - Body groundBelow 1 ohms
P42-2 (GND) - Body groundBelow 1 ohms

Fig. 25: Identifying D27, D28 Driver Seat ECU Connector Terminals And Power Seat Sensor
Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS AND CONNECTOR