Turn ignition and nothing, new starter new battery

if it cranks over-it may be an ignition system fault/ if you turn the key and nothing happens at all with a good battery-it may be a bad starter motor-the starter motor has a very small wire connection not like the big fat starter motor battery connection-it is small and comes from the ignition switch - just apply 12 volts from the battery to that connector terminal and the motor will crank-key off it will not start-turn key to ignition on- it will start, so be in park and block the wheels and do not make a mistake

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

I have a 93 pathfinder SE 4X4 automatic transmission that had full power, new starter and battery. Sometimes it will start and sometimes not. By passed starter relay by adding push button start and it started 6-8 times then nothing. I finally figured out that it was the neutral safety or inhibitor switch on the 4 wheel drive shifter. Just an idea..good luck

Starter Fuse? Possible failed ignition switch. Loose Cables on battery or starter. Starter not grounding properly. Bad starter Relay? Use Voltmeter check voltage going to main starter wire while someone cranks the motor if not power check power to starter relay while cranking if no power suspect ignition switch.

Possible bad ignition switch. Dont confuse the switch with key cyl,

The ignition switch attached to the column is probally bad, check the small wire to the sloenoid for battery when the key is turned to the start postion, if no battery, your not getting power from the ignition switch to the starter solenoid.

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.

Solenoid was not mentioned as replaced.

If it was not part of new starter...that's the culprit.

Ignition switch (smaller wire) activates the solenoid (heavier wire) which in turn activates the (high current) starter.

It could be the ignition going out. To test the ignition you would have to get a volt meter and find the hot wire to the ignition. When nothing happens when you turn the key, test the hot wire going out of the ignition that eventually goes to the starter. Your ignition is just like a light switch, just a little more complex. You will have to find the wire that connects the switch to the starter to see if the switch is working properly. If when you try to start the car see how many volts you are getting. It should be at 0 until you try to start the car. then it should jump up to either 12 or 24 volts depending on what your start used to start the vehicle. A lose wire from the battery can cause these same problems however. I would start with that and make sure you have good clean battery posts and connections. Then check to make sure they are tight. Then get into the ignition switch checks.