Ran into an issue about two weeks ago. Came out of a store and my PATS had disabled my engine (fast blinking theft light). I scoured all the threads and tried all the tips and tricks after before and after having it towed home. Finally had it towed to my trusted shop. They went through it and eventually found both factory original keys had become deprogrammed. They reprogrammed them and it was starting just fine, kept it overnight and drove it to ensure no issues. Picked it up, paid only a hour shop fee. Ran errands and the same PATS issue happened after one. Guy from the shop came out because I was still close. He thought it was strange but unhooked the PATS connection (white connectors) in the panel underneath the steering column. Started fine after that no flashing “theft”. Drove home and parked went to start up and the save PATS issue happened. These time I unhooked and reconnected the same connection and it started right up again no issues. Went to a job site worked and the same issue happened again. This time the connection trick isn’t working and seems the keys might be deprogrammed again. Had it towed back to the shop but after hours and now I’m just racking my brain/looking at all the forums again to find an answer and can’t seem to find one. Waiting for the shop to open tomorrow but just want to know if anyone else has had this issue? It seems really strange to have both factory keys become deprogrammed. I’m at a loss and tired of not having my excursion, looking for a solution and wondering if even when fixed should/could I just disable the PATS to make sure it doesn’t happen again and leave me stranded?

 

Fortunately, the actual PATS fuel cut stuff comes from the PCM and it is very easily defeated; either with a chip or with a PCM (Powertrain Control Module) reflash to disable the PATS and make it like an F250-F550.

The PATS module under the dash simply takes the key transponder data and then supplies the PCM with a matched code allowing the PCM to keep the engine running. Once the PCM has been reflashed to non-PATS or a chip with non-PATS programming is installed, the PATS module can be unplugged to keep the "THEFT" light from flashing.

I suspect that it's not a key "deprogramming" issue but a failing PATS module that is like an internet router that starts requiring reboots......

 

Good information. I have 2 keys coming for another Ford vehicle...Ford Edge Limited...with the PAT system which I will be programing them through Forscan given we only have one key and our 16 year old daughter just started driving it on Monday. The wife's Excursion Limited also has the PAT system which we have 2 keys for...thought about programing another, but we'll see what happens with Forscan on the Edge.

Out of curiosity, what's involved in replacing the PATS module if they go bad...

 

I can only vouch for the 7.3L Excursion PATS as I know how it works.....anything newer is a mystery.

Any 7.3L Excursion PATS module will be interchangeable but the 30 minute programming relearn has to be done to get the PCM/PATS to work. These modules are 22+ years old now. I don't know if they can be repaired when they **** the bed.

 

You can always try this

https://forum.gopowerhungry.com/foru...ead.php?t=2346

 

So one could get a PATS module from another Excursion and it should work with the programming, which I assume would be like what's mentioned in your other post below.


I've had to do this on occasion...sometimes not...when I attach the SCT to the OBII, which is not that often...