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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.
AIR SUS:
Fig. 125: Data List Value Description
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
d. Check that the steering wheel turning angle value of the steering angle position sensor displayed on
the hand-held tester changes when turning the steering wheel.
Standard:
Steering wheel turning angle value changes.
NG: Go to step 2
OK: REPLACE SUSPENSION CONTROL ECU (SEE REPLACEMENT
)
2.CHECK DIAGNOSTIC CODE OUTPUT
a. Check if the normal system code is output in the CAN communication system (SEE
SUSPENSION CONTROL ECU COMMUNICATION STOP MODE
).
OK:
No DTC is output in the CAN communication system.
NG: REPAIR CIRCUIT INDICATED BY OUTPUT CODE
OK:Go to next step
3.CHECK HARNESS AND CONNECTOR (STEERING SENSOR POWER SOURCE)
a. Disconnect the steering sensor S16 connector.
b. Turn the ignition switch to the ON position.
c. Measure the voltage according to the value (s) in the table below.
TESTER CONNECTION STANDARD SPECIFIED CONDITION
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
Tester ConnectionSpecified Condition
S16-1 (IG1) - S16-2 (ESS)10 to 14 V
S16-3 (BAT) - S16-2 (ESS)10 to 14 V
Page 610 of 4500
Fig. 126: Identifying Steering Sensor S16 Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
OK: REPLACE STEERING SENSOR (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
The height control switch turns on when it is pressed to the "HIGH" side and turns off when pressed to the
"NORM" side. The ECU detects the height control switch condition and raises or lowers the vehicle height
accordingly.
B
y controlling the height control switch, the vehicle height can be set 30 mm (1.18 in.) higher in "HIGH" mode.
Page 611 of 4500
Fig. 127: DTC C1786 Detecting Condition And Trouble Area
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
HINT:
DTC C1786 is output only in the test mode.
WIRING DIAGRAM
Fig. 128: Height Control Switch 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.
AIRSUS:
Page 612 of 4500
Fig. 129: Data List Value - Air sus
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
d. Check that the value displayed on the hand-held tester changes by pressing the height control
switch "HIGH" or "NORM" button.
OK:
Height control switch value changes.
NG: Go to step 2
OK: REPLACE SUSPENSION CONTROL ECU (SEE REPLACEMENT
)
2.INSPECT HEIGHT CONTROL SWITCH
a. Disconnect the height control switch connector.
b. Measure the resistance according to the value (s) in the table below.
TESTER CONNECTION STANDARD SPECIFIED CONDITION
NG: REPLACE HEIGHT CONTROL SWITCH
OK:Go to next step
Switch ConditionTester ConnectionSpecified Condition
"HIGH"2 (IGH) - 4 (HSW)Below 1 ohms
"NORM"2 (IGH) - 4 (HSW)10 Kohms or higher
Page 613 of 4500
Fig. 130: Identifying Height Control Switch Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
3.CHECK HARNESS AND CONNECTOR (SUSPENSION CONTROL ECU - HEIGHT
CONTROL SWITCH) (SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
a. Disconnect the suspension control ECU A20 connector.
b. Measure the resistance according to the value (s) in the table below.
TESTER CONNECTION STANDARD SPECIFIED CONDITION
Tester ConnectionSpecified Condition
A20-15 (HSW) - H21-4 (HSW)Below 1 ohms
A20-15 (HSW) - Body ground10 Kohms or higher
Page 614 of 4500
Fig. 131: Identifying Suspension Control ECU Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
Page 615 of 4500
Fig. 132: Identifying Height Control Switch 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 (HEIGHT CONTROL SWITCH - BODY GROUND)
(SEE ELECTRONIC CIRCUIT INSPECTION PROCEDURE
)
a. Measure the resistance according to the value (s) in the table below.
TESTER CONNECTION STANDARD SPECIFIED CONDITION
Tester ConnectionSpecified Condition
H21-2 (IGN) - Body groundBelow 1 ohms
Page 616 of 4500
Fig. 133: Identifying Height Control Switch Connector Terminals
Courtesy of TOYOTA MOTOR SALES, U.S.A., INC.
NG: REPAIR OR REPLACE HARNESS OR CONNECTOR
OK: REPLACE SUSPENSION CONTROL ECU (SEE REPLACEMENT
)
CIRCUIT DESCRIPTION
The absorber control switch is used to select the attenuation modes of the shock absorber. 2 levels of
attenuation, "SPORT" and "NORM", are available.