I want to remove the security in my lexus 90 - 1990 Lexus LS 400

I have a 2005 ES330!

The dealership does all my repairs, but I found this.

This is how I reset the security system each time after disconnecting the battery:

1. Insert master key (non-remote master) into driver's side door.
2. Remove key.
3. Insert master remote key into driver's side door.
4. Remove key.
5. Insert master key (non-remote master) into ignition.
6. Remove key.
7. Insert master remote key into ignition.
8. Remove key.

The is additional information in the link. If that doesn't work, the best place to ask would be the Club Lexus forum.

https://www.google.com/search?q=2001+lexus+es300+security+reset

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Two 8mm bolts secure this fuse to fuse box. They are accessed from under the fuse bx which will require removing the box itselt from location near battery and inverting to undo.

There are 3 steps(1) first them to 29 ft.lbs.in sequence(2) torque to 90 degrees in sequence (3) torque to 90 degrees in sequence again, then re-check the final torque in sequence.

put the seat in the full back position remove the two front bolts securing it to the floor, move it all the way forward now, remove the two rear bolts securing it to the floor now tip the seat back allowing it to rest on the back seat. make sure there is no additional wiring plugged in. use the recline function the make the seat flatter, now with two people roll the seat and remove throught the front door utilizing the rear for the helper

1999 Lexus ES300 (3.0L, VIN F, 5th digit, 1MZFE engine)

Thermostat on 1mz-FE Engine

1. Disconnect the negative battery cable. Wait at least 90 seconds before performing any other work.
2. Drain the engine coolant.
3. Remove the battery.
4. Remove the air cleaner inlet assembly.
5. Remove the air cleaner assembly with hose.
6. Remove the air cleaner bracket.
7. Remove the air cleaner inlet No. 1.
8. Disconnect the radiator hose outlet.
9. Remove the bolt and water inlet pipe.
10. Remove the O-ring from the water inlet pipe.
11. Remove the 3 bolts and water inlet.
12. Remove the thermostat.

Fig. Correct alignment of the thermostat jiggle valve.-1MZ-FE and 3MZ-FE engines

Hope helps (remember to rate and comment this).

1. Install or connect the following:
   
   • Spring seat. Tighten the new upper strut retaining nut to 36 ft. lbs. (49 Nm).
     
2. Remove the strut from the vise and disassemble the securing nuts and bolt.
   
3. Rotate the upper support so the lowest bolt on the support aligns with the projection part of the lower spring.
   

1. Install or connect the following:
2. Strut and tighten the strut to body bolts to 59 ft. lbs. (80 Nm).
   

• Strut to the steering knuckle and tighten the bolts to 156 ft. lbs. (211 Nm).
  

To install:

1. Install the lower ball joint onto the steering knuckle and tighten nut to 90 ft. lbs. (123 Nm). Install new cotter pin.
   

we use to suction cus and a strap to keep the window up while removing the regulator they can be tricky to get out there are several bolts and 2 clips? due to the cosyt of this unit you may want to spend the extra $90 and let a tech do it? hope this helps

I don't have a 90 LS 400 so I'm not 100% sure this is what the inside of your car looks like but I think this will do it for you: http://www.lexls.com/tutorials/audio/headunit.html

Looks a little intimidating but it's not too bad.  Good luck!

H2O SENSOR OR TROTTLE BODY BAD

SMELL LIKE GAS could be the O2sensor

holding your feet on the gas keeps the trottlebody open mite be the trottlebodysensor