Suspension Control System: Overview Lexus GX J120

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1. JACK OR LIFT UP AND DOWN When jacking up or lifting up, stop operating the air suspension control system by pressing the height control OFF switch.
2. DISCONNECT AND CONNECT HEIGHT CONTROL TUBE NOTE: Disconnecting and connecting the height control tube should be performed by hand to prevent foreign objects from entering. Never damage the height control tube. Disconnect the height control tube. Disconnect the height control tube. Pinch "A" of the connector No. 1 and pull it out from the housing. Set SST to the tube. SST 09730-00010 Insert SST into the housing to expand the claw of plug or tube connector in the housing. Pull out the tube with SST inserted. NOTE: Never pull the tube forcibly. Insert a flat-head thin-bladed screwdriver into the circular hole on the housing, and remove connector No. 2, the 2 O-rings and the plate from the housing. HINT: O-ring, plate and connector No. 2 are non-reusable parts. Installs 2 O-rings and the plate. NOTE: When replacing the parts on which the tube to be installed with a new one, it is not necessary to perform the procedure for installation. Apply MP grease to 2 new O-rings and plate, and install them to the straight tube or equivalent. NOTE: Install the plate between the O-rings. Never adhere foreign object to the O-rings and the height control tube to prevent air leaks. Insert the tube on which 2 O-rings and a plate are installed into the housing, and then push it in lightly with rolled up cardboard. Push the connector No. 2 into the housing to the position where a clicking sound is heard. Install the height control tube. Push the tube and connector No. 1 into the housing to the position where a clicking sound is heard. NOTE: Slide the phase of the housing port from that of the connector No. 1 claw 90° to install. Pull the tube lightly to make sure that it is securely connected.

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1. ADJUST STANDARD VEHICLE HEIGHT Release the parking brake and stabilize the suspensions by pushing up and down the corners of the vehicle. Move the shift lever to the "N" position and settle the tires by moving the vehicle back and forth by hand. Start the engine. On the height control switch, first press "HIGH" to raise the vehicle height, and then change the switch to "LOW" to lower it. Perform this operation one more time. NOTE: Make sure to release the parking brake and move the shift lever to the "N" position.
2. INSPECT TIRE (SEE «WHEEL AND TIRE SYSTEM»(ref-228790-S11193813852006041100000) )
3. MEASURE VEHICLE HEIGHT (SEE «FRONT WHEEL ALIGNMENT»(ref-228788-S15882064162006041100000) )
4. OPERATE HEIGHT CONTROL SWITCH AND CHECK CHANGE OF VEHICLE HEIGHT Start the engine and change the height control switch from the NORMAL position to the HIGH and LOW position. Check the time until the height adjustment is completed and the amount of change in the vehicle height. Adjustment time ADJUSTMENT TIME From operation of height control switch to start of compressor. Approx. 2 sec. From start of compressor to completion of height adjustment. 15 - 20 sec (High position) Amount of change in vehicle height HIGH position: 40 mm (1.57 in.) LOW position: -20 mm (-0.79 in.) With the vehicle in the HIGH position height adjustment, start the engine and change the height control switch from the HIGH and LOW position to the NORMAL position. Check the time until the height adjustment is completed and the amount of change in the vehicle height. Adjustment time ADJUSTMENT TIME From operation of height control switch to open of exhaust valve. Approx. 2 sec. From open of exhaust valve to completion of height adjustment. 10 - 15 sec. (HIGH position) Amount of change in vehicle height HIGH position: 40 mm (1.57 in.) LOW position: -20 mm (-0.79 in.)
5. CHECK CONNECTIONS OF TUBES FOR AIR LEAKAGE Set the height control switch in the HIGH position and raise the vehicle height. Stop the engine. Apply soapy water to the connections of the tubes and check if there is any air leakage.
6. ADJUST VEHICLE HEIGHT NOTE: While adjusting the vehicle height, never get on and off or load and unload the vehicle which causes the vehicle height to be changed. Suspend the vehicle height control by pressing the height control OFF switch. Put the vehicle in a level state. Measure again the vehicle height (C - D measurement) on the right side and left side. Standard vehicle height value: See «FRONT WHEEL ALIGNMENT»(ref-228788-S15882064162006041100000). Difference between the right side and the left side: 10 mm (0.39 in.) or less If the actual vehicle height differs from the vehicle height (C - D measurement), adjust it by jacking up the frame, etc. When using the hand-held tester: Turn the ignition switch to ON or ACC. Using the hand-held tester, measure each vehicle height value of the right side and the left side sensors. Difference between the tester value and vehicle height (C - D measurement): 5 mm (0.20 in.) or less Difference between the right side and the left side: 5 mm (0.20 in.) or less When not using the hand-held tester: Disconnect the connector of the height control sensor. Connect three 1.5 V dry cell batteries in series. Connect the battery positive (+) and negative (-) to the terminals (Scheme 13) Standard: VOLTAGE Position Voltage High 2.31 - 3.81 V Normal 2.31 +/- 0.04 V Low 39 - 2.31 V Difference between the right side and the left side: 0.06 V or less If the value in ( e ) or ( f ) differs from the vehicle height (C - D measurement), adjust it by following the procedures below: Loosen the nut. Move the height control sensor link up and down along the slotted hole of the bracket. Adjust the vehicle height to the vehicle height (C - D measurement) while checking the value on the hand-held tester or the voltmeter. Tighten the nut. Torque: 5.4 N.m (55 kgf.cm, 48 in.lbf) If the vehicle height cannot be adjusted by performing ( g ), adjust it again by following the procedures below: Loosen the 2 lock nuts of the height control sensor link. Adjust the vehicle height to the vehicle height (C - D measurement) by turning the link while checking the value on the hand-held tester or the voltmeter. Tighten the 2 lock nuts. Torque: 5.4 N.m (55 kgf.cm, 48 in.lbf) Check that the lengths of the screw parts, "A" in (Scheme 16), are within the standard value. Standard length: 6.5 - 15.0 mm (0.26 - 0.59 in.) Operate the height control (From normal position to high position, and from high position to normal position) Measure again the vehicle height (C - D measurement) on the right side and left side. Check that the vehicle height (C - D measurement) and the difference between the right side and the left side fall within the specification. HINT: If the values are out of the standard, perform the procedure from ( d ) to ( k ) again.

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See also:
• LOCATION