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1999 Lincoln TownCar security system anti-scan?

I have a 1999 Lincoln Town Car and it cranks but no start. The battery died over the winter and I attempted to get a jump. Since no start I sent it to my local trusted shop and they told me there’s no fuel, fire and no communication to PCM, but it cranks. They did not want to get involved and dropped it back home no charge. After many hours of research on Youtube, I checked all fuses, switched corresponding relays and connected my own scan tool and still nothing. I even hired a private mechanic to check it out and he said “sounds like your security system”. He suggested for me to go to a auto electronics place and have them program the key. I called a local locksmith and he brought over two devices and made another key as well. He was able to clear the 6 keys that were in the system and place the 2 keys (original and a copy he made), but the security system did not reset still. He read the manual for errors codes and said “the security system is in an anti-scan mode”. What can I do now besides go to my local Ford dealership. HELP!!! Thanks in advance.

Does it have an aftermarket alarm?

You have personally verified that BOTH spark and fuel pressure are missing along with an injector pulse?

Does ‘all fuses’ mean both underhood and in-dash?

I saw one guy test for spark, and I had the key on, not cranking, and check the schrader vale on the fuel rail and little pressure.

Yes under the hood and dash.

No sir. My friend bought and programmed a alarm fob and it opens/closes door/trunk and panic alarm, but I was told it is factory based.

Usually alarms with kill switches either kill fuel delivery, or spark. Usually not both, so if you’re missing both, it’s unlikely to be an alarm, aftermarket or otherwise.

What exactly do you mean by “hired a private mechanic to check it out?” Was this a legit mechanic who actually owns a shop, or was it some dude working out of a minivan?

Why not go to your local Ford dealer? They have the equipment and expertise to quickly solve this.

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I’ve heard from many people that they are not reliable and difficult to work with.

A legit guy who when finished his work came to me.

That is why why a dealer might be best, if factory system they have the tools to diagnose and correct the problem. They will charge you for a diagnosis, if you choose to have them correct the problem they will stand behind it.
Easy to deal with, if you don’t want them to repair, just pay for the diagnosis and leave.

I have no idea how the aftermarket alarm is configured. I have a factory manual for 98 LIncoln and as far as the factory security system goes it has nothing to do with spark or fuel according to the 6 pages of schematics. Whether your 99 factory system is the same I do not know.

Without car in hand I have no answers but I suspect lack of spark (if the case) and fuel pressure may be related to something else other tha the alarm.

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I’d say “no communication to PCM” should be #1 on your list

Make sure it’s not the guy and/or his equipment

Not all mechanics are equal

Not all scanners/code readers can communicate with all control modules and/or vehicles

Once you’re able to properly communicate, then you should be able to determine . . . via the appropriate pids . . . if the engine is being authorized to start or not. it should be crystal clear

Have you verified power at the data link connector . . . ?!

Please don’t take this question the wrong way . . .

the inertial fuel shut-off switch isn’t tripped, is it . . . ?!

You really need to hook up a gauge

So what is the deal with the battery right now . . . ?!

Have you replaced it?

Have you recharged the old battery, and it tests good?

Or are you using a jumper, while trying to start the engine?

Is the engine even cranking over fast enough to start . . . ?!

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Almost certainly your alarm system is preventing the car from starting. This mode means the alarm system has detected an improper signal and temporarily shut down. This feature is there to prevent someone from blasting your car with key code combinations until it opens. It will reset after a predetermined delay and resume scanning for valid key codes.

Either the keys are not properly coded to the car or the controller is buggered up. You may have multiple problems if the last guy improperly coded the keys to the car, compounding the issue. IMO, you need to solve this first as it is preventing the car from starting regardless of any other issues. Hopefully it is the only problem…

db4690, no flames here didn’t take q’s wrongly I just want to get started again and driving.
Yes a fuel pressure gauge was used and while cranking no pressure.
Yes the battery was charged and is in good health, just got low on power while diags and starting.

TwinTurbo, I am heavily considering taking it to the dealer for a proper diag. One of the keys is an original. I had a copy made that I was driving around in before the battery died. The locksmith made me another and he said that he made it with a different “personality” than the original and both keys are in the system.

Thanks to everyone, stay safe.

UPDATE: Finally “bit the bullet” and had it towed to a dealer 40 miles away. They called today and said it was a module for the PCM and a module for the airbags, as the rear was down from previous tow. When I find out which modules I will update.

Thanks everyone!