sensor LEXUS LS430 2003 Factory Repair Manual

CIRCUIT DESCRIPTION
The acceleration sensors (assy) detect up-and-down acceleration of the vehicle. The acceleration sensors (assy)
3 in total are mounted in the absorber control ECU, at the forward of the glove compartment door at the
instrument panel safety pad position and in the rear luggage, and detect up-and down acceleration of the
vehicle, respectively. The acceleration sensors (assy) convert the resistance into electrical signals and output to
the absorber control ECU.
Fig. 47: DTC C1715 And DTC C1793 DTC Detecting Condition And Trouble Area

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
HINT:
DTCs C1715 and C1791 are for the right front acceleration sensor assy.
DTCs C1716 and C1792 are for the left front acceleration sensor (left front acceleration sensor is a built-
in equipment).
DTCs C1717 and C1793 are for the rear acceleration sensor.
DTCs C1791, C1792 and C1793 are output only in the test mode.
WIRING DIAGRAM

Fig. 48: Rear Acceleration Sensor Wiring Diagram
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.READ VALUE ON HAND-HELD TESTER
a. Connect the hand-held tester to the DLC3.
b. Turn the ignition switch to the ON position and turn the hand-held tester main switch on.
c. Select the item below in the DATA LIST and read its value displayed on the hand-held tester.
DATA LIST AIR SUS
d. Check that the acceleration value of the acceleration sensor observed on the hand-held tester
changes when the vehicle is bounced.
Standard:
ItemNormal condition
G (UP & DOWN) FR (Right front acceleration sensor)0 +/- 31.9 mm/s2 at still condition
G (UP & DOWN) FL (Left front acceleration sensor)0 +/- 31.9 mm/s2 at still condition
G (UP & DOWN) R (Rear acceleration sensor)0 +/- 31.9 mm/s2 at still condition

Acceleration value must change.
RESULT DESCRIPTION
B: Go to step 2
C: Go to step 3
D: REPLACE LEFT FRONT ACCELERATION SENSOR
HINT:
For the left front acceleration sensor failure, replace the suspension control ECU.
A: REPLACE SUSPENSION CONTROL ECU (SEE REPLACEMENT
)
2.INSPECT HEIGHT CONTROL SENSOR SUB-ASSY FRONT RH
a. Remove the height control sensor sub-assy front RH.
b. Connect 3 dry batteries of 1.5 V in series.
c. Connect terminal 1 (SHB) to the batteries' positive (+) terminal, and terminal 4 (SHG) to the
batteries' negative (-) terminal, then apply voltage of approximately 4.5 V between terminals 4
(SHG) and 3 (SGFR) for the following conditions.
SENSOR CONDITION AND VOLTAGE SPECIFICATIONS
OKA
NG (right front acceleration sensor)B
NG (rear acceleration sensor)C
NG (left front acceleration sensor)D
Sensor conditionVoltage
Sensor stationaryApprox. 2.3 V
Sensor vibrating verticallyChange between approx. 1.0 to 4.0 V

Fig. 49: Inspecting Height Control Sensor Sub-Assy Front RH
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

HINT:
When the acceleration sensor assy is tilted, it may output a different value.
NG: REPLACE HEIGHT CONTROL SENSOR SUB-ASSY FRONT RH (SEE REPLACEMENT
)
OK: Go to step 4
3.INSPECT ACCELERATION SENSOR
a. Remove the acceleration sensor.
b. Connect 3 dry batteries of 1.5 V in series.
c. Connect terminal 3 (VGS) to the batteries' positive (+) terminal, and terminal 2 (GGND) to the
batteries' negative (-) terminal, then apply voltage of approximately 4.5 V between terminals 1
(GL1) and 2 (GGND) for the following conditions.
SENSOR CONDITION AND VOLTAGE SPECIFICATIONS
Sensor conditionVoltage
Sensor stationaryApprox. 2.3 V
Sensor vibrating verticallyChange between approx. 1.0 to 4.0 V

Fig. 50: Inspecting Acceleration Sensor
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.

HINT:
When the acceleration sensor is tilted, it may output the different value.
NG: REPLACE ACCELERATION SENSOR
OK:Go to next step
4.CHECK HARNESS AND CONNECTOR (ACCELERATION SENSOR - SUSPENSION
CONTROL ECU) (SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
a. Disconnect the suspension control ECU A20 or A22 connector.
b. Measure the resistance according to the value (s) in the table below.
Fig. 51: Identifying Suspension Control ECU Connector Terminals

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
TESTER CONNECTION STANDARD SPECIFIED CONDITION STANDARD (FRONT RH)
Fig. 52: Identifying Height Control Sensor Connector Terminals

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
TESTER CONNECTION STANDARD SPECIFIED CONDITION STANDARD (REAR)
Tester ConnectionSpecified Condition
A20-20 (SBR1) - H14-1 (SHB)Below 1 ohms
A20-21 (SGR1) - H14-4 (SHG)Below 1 ohms
A22-29 (SGFL) - H14-3 (SGFR)Below 1 ohms
A20-20 (SBR1) - Body ground10 Kohms or higher
A20-21 (SGR1) - Body ground10 Kohms or higher
A22-29 (SGFL) - Body ground10 Kohms or higher
Tester ConnectionSpecified Condition
A22-12 (SGR3) - A32-2 (GGND)Below 1 ohms

NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE SUSPENSION CONTROL ECU (SEE REPLACEMENT
)
Fig. 53: Identifying Height Control Sensor Connector Terminals

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
A22-15 (SBR3) - A32-3 (VGS)Below 1 ohms
A22-27 (SGRR) - A32-1 (GL1)Below 1 ohms
A22-12 (SGR3) - Body ground10 Kohms or higher
A22-15 (SBR3) - Body ground10 Kohms or higher
A22-27 (SGRR) - Body ground10 Kohms or higher

10.INSPECT FOR CLOGGED AIR TUBE
a. Check the air tube visually for a clog or damage (see ON
-VEHICLE INSPECTION ).
OK:
Air tube is not clogged or damaged.
NG: REPAIR OR REPLACE AIR TUBE
OK: REPLACE SUSPENSION CONTROL ECU (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
The signal from the suspension control ECU operates the AIR SUS relay and the height control compressor
motor starts.
The height control compressor motor operates until the targeted vehicle height is reached. Then the height
control sensor sub-assy sends the signal to the suspension control ECU, and stops the height control compressor
motor.
Fig. 104: DTC C1751 And DTC C1752 Detecting Condition And Trouble Area

Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
INSPECTION PROCEDURE
1.CHECK HEIGHT CONTROL COMPRESSOR CIRCUIT (SEE DTC C1742 HEIGHT
CONTROL COMPRESSOR CIRCUIT )
2.CHECK AIR LEAKAGE (SEE ON
-VEHICLE INSPECTION )
OK:
No leaks