Security Systems won't let me start my car

Andrew this has nothing to do with PATS immobilizer ,this is for resetting the vehicles contents theft system.

If You need to reset the anti theft system in Your 2007 Lincoln MKZ it is a pretty easy to do it just takes a few minutes. You should be able to reset it without using any special tools as well. All You need to do is turn the vehicle from off to on 8 times quickly without starting it and then leave it in the on position. You will then watch the locks in the car automatically cycle to lock and unlock. After that press and hold any of the buttons on Your key fob for 20 seconds until You har a beep. After that You can turn the vehicle off then start it again. If You have multiple problems with Your anti-theft system there may be a body control module problem that needs to be addressed by Lincoln.

Hello. It seems your key fob has a low battery. This will cause it to, partially, malfunction; making the car 'think' it is about to be stolen. Attain a new battery for your key fob. Good luck and keep me informed; if you want to.

You can't do anything ,unless you have diagnostic computer . Check codes , program key etc.... Call a mobile lock smith or have towed to the dealer .

Locate your second key fob -
Try using that key fob -

if it does not work, and you can verify the Batteries in both Fob's are good - it could be a couple different things.

1. your security system control box may be 'bad'.
2. their is a 'ring' around the key area that are notorious for going bad and preventing the car from starting - however...they don't prevent the key fob from remotely opening the door locks.
3. The power feeding the security system is interrupted (blown fuse, etc) -

I would do the following:

1. Check the second fob and see if it works - If it does you have a bad #1 key fob (or battery).
2. Check ALL of the fuses (in the dashboard Drivers side access panel) AND under hood - Check even those not labeled security - as there are often fuses that feed more than one item, but are only labeled for one item.
3. Try going inside the car, shut all the doors, and lock/unlock the car five or six times using the interior control - I believe this is supposed to reset the unit.
I could be wrong - you can look this up. It might be that you have to do this with the key fob but I can't recall.

Give those things a shot. Also, make 100% sure all of the doors, hood, trunk, etc are fully closed.

I'd just about bet you have a bad key fob - finding #2 is the key here.

Beyond that - it's probably a trip to the junkyard for a new security module and matching set of key fobs - But long before getting involved in that - I'd bet you have a bad key fob or blown fuse -

Security Modules and key fob's are not universally replaceable, are extremely difficult to work with (for those without VIDA [Volvo Diagnostic software] and programming capabilities) and have to be programmed to work with the control unit to which assigned.

Need to go dealer and have car computer reflashed and radio reprogrammed

The security light is a indicator that one of the parts of the antitheft system is failing, this then disables parts of the car due to the antitheft thinking that the car is being stolen. You may have broken something while turning the ignition when trying to learn your key fob. Did you make sure to pull the radio fuse before trying the key fob process? A lot of GM's 2000 to 2004ish ran the antitheft thru the radio. Its really hard to tell. Here is a link that explains the anti theft system. A lot of information and some ways to get around the system.

http://vatspasslockpasskeysecurityhelp.yolasite.com/

Here is what i found for reprogramming your key fob remote

1. Be sure ignition is OFF.

2. Remove RADIO fuse from fuse box. Fuse will be number 17 and located at LH side of instrument panel.

3. Turn ignition from OFF to RUN 3 times within 5 seconds ending in the RUN position. Off is the position where you can remove your key and Run is the position shy of starting your vehicle (do not crank engine or start vehicle). Be sure you are turning the key from off to run quickly.

4. Doors will Lock and Unlock indicating entry into programming mode.

5. Hold Lock and Unlock at the same time on first remote for approximately 15 seconds. Vehicle will respond by locking and unlocking doors indicating successful programming.

6. Repeat step 5 for each additional remote including working remotes.

7. Switch ignition off. Replace RADIO fuse. Test all remotes.

If the passkey is messed up, there will be a light on the dash that says security, or have a picture of a car with a lock thru it. If there is no light when the key is turned forward, then its NOT a passkey problem.

Anti Theft System - inmobilizer is actovated. Need disarm to start engine. Have you another key and fob? Try lock/unlock cycle with new key + fob. Your key may be corrupted.

Try also just unlocking the car with the key (not the fob) as soon as you unlock the door put the key in the ignition immediately and see if the car starts.

If you have your radio code it may be worth trying a total reset (leave the car unlocked) disconnect the battery and leave for 20 mins. then reconnect.

Hope help with this.

The security systems pass lock is disabling the vehicle. This usually happens when the ignition switch does not recognize the ignition key and/or a defective fob or the battery in the fob needs to be replaced. If you ignition key is too worn. This could possibly be your problem

Usually on the passat, if the immobiliser is on, there is a yellow key symbol flashing on the clocks as you try and start it. Do the doors unlock with the remote key? If no flashing light and the key fob working, i would be looking at possibly starter relay. This is either located under the fuse box or under a plastic cover near the windscreen under the bonnet. (hood)