2000 buick lesabre wont start change ignition starter switch ignition lock cylinder and still wont start

does the starter turn over

Do you mean won't crank or won't start? If it won't crank,and you don't see a SECURITY light on the dash,it could be the starter,or maybe the PRNDL switch(my bet is the starter,since GM can't build a decent starter or alternator). If you do see the SECURITY light,you are probably looking at replacing the ignition lock cylinder.If you are referring to a "cranks but no start" condition,you have to determine what is not working(no spark,no compression,or no fuel) to get a handle on the problem.

The light is on to indicate you have been locked out and the engine disabled. You must now have the dealer scan the system and determine the cause of the malfunction in the security system, it is likely the ignition lock cylinder key code reader that is defective.

Could be the key itself, the lock cylinder, or the Theft Deterrent Module that controls the whole system. This link explains the system and offers a very good way to just bypass the system permanently...
http://vatspasslockpasskeysecurityhelp.yolasite.com/

Hello: Make sure the battery cables are clean No corrosion, and tight. If the security light is not flashing when you try to start it, the have a helper hold the ignition switch in the start position and you go under the car and hit the starter (not to hard) near the end that goes into the engine, If it starts then you need a starter. If the security light flashes while trying to start you have a pass key problem

The coded key probably needs to relearn. Turn ignition to crank and release. Let sit in on position (engine off of coarse) for a full 10 min. turn off for 30 sec. and repeat 3 times engine should start. This procedure should take 30 min. so a booster is needed to maintain a full 12 volts. Do not attempt w/out a charger connected;

pass key needs replaced also leave ignition on for 30 minutes so pass key around lock cylinder can relearn

these cars have a antitheft system that will shut down fuel and crank. be sure to check to see if after the car ignition is on for 30 seconds and look to see if there is a security light on in the dash. if so then turn to crank if security light flashes your problem is that the chip in your key is not being transfered to the security module, so starter will not work. you will have to replace the pickup in the cylinder or bypass the security with proper resister

the V.A,T.S. ignition lock cylinder is starting to fail , will need ign, cylinder and two new keysS.R. Peace

I have same problem with buick lesabre 2002 and is not starter.