I have a 2002 F150 XLT 4x4 which is driving me nuts! From time to time, it will crank but not start. When this occurs, the theft light flashes rapidly. I have checked fuses, relays, harnesses, etc. I have received and tried several suggestions from this forum and from my local dealer, but the problem persists. The dealer says they can't help me for sure until it is completely DOA. Is there a way for me to supply power to the PCM without damaging it so I can by-pass PATS? Thanks for any and all advice.

 

Not sure how you figure you can bypass the PATS by "supplying power to the PCM". It doesn't work like that, it's a passive system.

When you turn the key, a signal from the module is sent asking "Key, are you there and the correct one?" Then key responds with "Yes, I am the correct one, here are my credentials". Then the module does it's check, "Yes, the key responded with the correct information. PCM, you can allow the truck to start".

What have you tried besides what's listed? Have you tried different keys?

 

Hello. I only have one key. I have another lock w/2 keys which I would have to have the dealer flash, but the dealer says that will not necessarily correct the problem; even if I have them cut me two keys for the lock I have now, it will be $115 either way. I realize PATS is passive, but if I can by-pass it to the PCM won't my truck function then? Thanks for the reply!

 

I agree with the dealership as far as the other ignition not fixing the problem. There is not really a way to disable it how you are thinking you can. That is the reason for the the system. If it could be easily disabled or tricked it would not be doing it's job.

I do believe that a custom tune like that of the SCT has the ability to remove the PATS requirement, but we are talking more money than what the dealer could do to fix it (most likely). The pre-loaded tunes do not have this ability as far as I know.

 

Unfortunately the PATS is preventing me from using my truck, that is why I am looking for a way to by-pass it.

 

Some auto start systems use a PATS disable feature. I have it on 2 of my vehicle, where the autostart was installed, so now I can use the regular keys that aren't chipped. I don't have a schematic to check, but with the ring and its sensor, when hooked correctly, should do your bypass. Check with an installation center. That may be your best bet to get rid of the PATS requirement.

 

Thanks to all of you folks for your input and assistance. I will check with my local remote start installer to see if they know anything about this problem.