Different PATS problem
 

2004 Ford Ranger, 2.3L, manual transmission, manual locks and windows.

Truck sat for 9 months and battery died. Charged it up but now I'm getting a PATS (anti-theft) issue that seems unusual. The light blinks once every two seconds like it should with the key out. When I put the key in and try to start, everything comes on, but the PATS light continues to just blink once every 2 seconds and the truck wont start. It is not the rapid blink like it is the wrong key and waiting a minute does not give a code. I have 3 programmed keys and the same thing happens with all of them. I just changed the "transceiver" (the ring around the ignition) but it still does the same thing. Any thoughts? Thank you

Is battery OK?
If it sat for 9 months connected to vehicle its "toast"
Car batteries are made for fast discharge and fast recharge, they will get internal shorts if the are fully discharged
So if its holding a charge now shop for battery sale, because it won't last long

PATS is voltage senistive
Disconnect battery and wait 5min
Reconnect it
See if PATS resets

Did you "Jump Start" it?

Also a no-no on any vehicle after 1990 or so, you can do it and 9 times out of 10 its OK, but its that one time that it bites you, lol
Disconnect one battery cable on the "dead" battery
Charge battery with jumper cables from the Running vehicle, just for a minute or two
Shut off running vehicle
Hook dead battery back up and jumper it to NON-running vehicle battery
Try to start dead vehicle
Unhook 1 jumper cable as soon as possible after start up

Electronics makes vehicles so much better now, some may disagree, but they didn't have to spend one(or two) Saturdays every month tuning up family engines or rebuilding carbs, trust me it sucks, "good ol' days" my a$$

But the price we pay is breaking old habits like the way we Jump dead battery vehicles, its just different, to avoid damaging one or both vehicle electric systems
And NEVER unhook a battery cable with engine running to see if alternator is working, lol

I did unhook the battery for an hour and try again and that didn't work. You might be right about the battery voltage not being good enough. I'll see if I can take that out of the equation somehow tomorrow. Thanks for the response!

I agree about the electronics. I put fuel injection on my 1979 Scout for that reason!

I made sure the truck had good voltage and still have the problem. The anti theft light blinks once every two seconds even after turning the key to the “on” position and everything else comes on. It’s like the PATS never sees a good key or bad key. Is there something that should prompt the PATS system to check the key? Maybe that is not working

Key on powers up the Cluster(where PATS is located) and that will cause it to test the key

PATS is passive anti-theft system
So its not an alarm, its not even active after it "tests the key"
It tests the key and sends the Computer(PCM) the "OK to start" data message then it shuts off until rebooted with key on

Yes, but in my case, it is like it never tests the key. The PATS light blinks every two seconds like normal without the key. When I put the key in and turn it to the "on" position, the instrument cluster comes on but the PATS light continues blinking once every two seconds. It never goes solid and stops blinking, and never blinks rapidly.

Sorry I had to leave and didn't mean to post that incomplete post

Rest is when you turn on the key, Fuse 10 in engine fuse box powers up and sends 12v to instrument cluster which tells PATS to initiate "read the key" so Theft Light should go off at that point

Check fuse 10 in cab fuse box
Also check fuse 9 and 33

Unfortunately if these fuses are OK then the instrument cluster or SJB(smart junction box, aka body computer) may be bad
Cluster can't not be "just swapped", it is "married" to the engine computer(2004-2011) when they were both installed at the factory
So a new cluster wouldn't plug and play, have to remarry them

Forscan software should be able to do that,