New battery new starter nothing happens when i turn the key

check if you have a starter relay . If so change it out . If not check that the battery posts and terminals are shiny clean and tight

I looked at info for your security system, it is starter motor disable. I didn't see 06 ford Taurus in my database, so I looked at 05.
Battery has a full charge and battery connections all good?
We can usually do some tests to see if starter motor will crank the engine, but, if the security is the problem, it still won't start.
You can check for applicable trouble codes? Try a different key?

check the starter

Hi! It sounds like a bad solenoid, or that you're not getting the 12 volts to the solenoid to engage the heavy amperage needed to turn thr starter motor.
When you say you bypass it,do you mean you are just crossing the large post of the solenoid with the battery cable connection at the starter?
When you turn the key,you should get 12 volts at least at the smaller post on the solenoid.If you have 12 volts there when the key is all the way to `start 'position,then the starter probably ought to be replaced.
This car being a 2000 is 13 yrs.old.Won't hurt to put a new starter on it.
don-ohio (:^)

fuses - including the eingine fuse itself,. otherwise you may want to tap on the starter while someone trys to turn it over,. otherwise remove, test (if good) replace starter) was the starter solenoid replaced with the starter? are all the connections including the battery ground cleaned/ inspected? You may have a bad starter or bad solenoid, even new (rebuilt) that can happen..
best regards
Ck

Try checking the oil, the low oil sensor will disable the ignition

your starter needs replacing not to hard of a job to do yourself

Check battery full charge, battery terminals are clean, cables aren't cracked, broken or corroded and alternator first.

Which your having replaced your starter with new already. If you're still getting nothing it sounds like a bad ignition switch.

They wear normally and need to be replaced. But as a helpful hint don't place excess keys or weighty trinkets on your ignition keys.

They wear on the seating of the key in the ignition and often promote failure in the ignition from bearing the dangling weight.

you say nothing happens sort of need more specifics, does it attenpt to rotate the engine? does the starter click? are all of the wires in the correct spots on the starter?
Is there powerat the starter?
have you checked your fuses?
can you rotete the engine by hand?

Check your courtesy fuse, battery connections or test battery itself.