Replaced ignition but truck won't start.

[Chantel Robertson]

Hello.
I am helping a friend try to get her truck back together. Her ex stole the keys to her 99 explorer and had to go to Pick-A-part to find a new ignition. Found one with a key and replaced the old one. Now the theft light is flashing and it won't turn over. It wants to but doesn't. It's her 40th birthday today and I would really love to get this done for her. Do I have to replace the entire computer? Pay a locksmith to come reprogram? Please help..

 

[974X4BLACKSPORT]

PATS (ppasssive anti theft syystem) has been activated which means the keyy has to be "coded" to the vehical.

 

[koda2000]

The new JY key you have has a chip in it. It's read and it's code is send to the PCM for verification. If the key's code is not recognized by the PCM the truck will not run, because the PCM will not enable the fuel injectors. It's called PATS (passive anti theft system).

 

[Chantel Robertson]

How do I fix this?

 

[koda2000]

A locksmith can reprogram the PCM. A Ford dealer can do the same, or you can do it yourself using ForScan (free software) a ELM327 interface and a laptop.

 

[Redmanss]

Short answer, yes, you're going to have to get it reprogrammed. Interestingly, here's a thread from last week with someone else who had an ex do them dirty. After Attempted Theft, Not starting. No obd2 codes

Easiest route is to get a locksmith that has the tools to reprogram the PATS codes.

 

[Chantel Robertson]

Can I go back to the auto wreckers and get another key ignition and pcm and replace them all?

 

[Chantel Robertson]

Can't afford to pay a locksmith..

 

[Jason94sport]

Then your going to run into many other issues. Call around for locksmiths. I'm sure you can find someone under $100 to do it. Most I have seen was $75 here.

 

[Chantel Robertson]

Frick...thanks guys.

 

[Mbrooks420]

If you get a matching PCM to the key, I would think PATS would be satisfied.

 

[German Engineer]

If you get a matching PCM to the key, I would think PATS would be satisfied.

I'm not sure, but I Imagine replacing the PCM with the one from the car he got the lock and key out of, would very likely have him run into other issues, like ending up not having the right PCM programming for the components of the car. Wouldn't he then end up having to reprogram the PCM?

 

[Mbrooks420]

I think it’d be fine as long as it were like and kind, IE, same motor, transmission, 2wd/4wd, ETC.

 

[CDW6212R]

Then your going to run into many other issues. Call around for locksmiths. I'm sure you can find someone under $100 to do it. Most I have seen was $75 here.

Ditto, the PCM module, PATS module, and keys are all matched(by the programming). You could swap all of them from another like truck, but that's much more trouble.

Be sure you end up with at least three good programmed PATS keys. You must have two to be able to program any new keys, so if you lose one, you better have two others.

The PATS module stores the key codes, it can hold eight. If it's brand new(empty), or has been erased(that's what a lock smith will do, or the ForScan and ELM327 interface can do), then any key will work(as the first). When there's one code stored, only the first is needed to add another. Then you have to have two to add more.

Erasing the old PATS codes is your goal, then you can do the self programming easily.

 

[koda2000]

With the free ForScan software download and a $20 ELM327 interface off Amazon, that's the cheapest, easiest way to go.

 

[Rick]

With the free ForScan software download and a $20 ELM327 interface off Amazon, that's the cheapest, easiest way to go.

Is there one you recommend? I checked Amazon and saw a bunch. One said specifically not for ForScan.

 

[Mbrooks420]

You gotta be careful with it. Most are just cloned chips and your results will vary. There is a recommended model near the end of the forscan thread I do believe.

 

[koda2000]

Is there one you recommend? I checked Amazon and saw a bunch. One said specifically not for ForScan.

Well, I'd recommend you DO NOT buy the one that says, "Not for ForScan". Someone here just recommended one here about a week ago. I'll see if I can find his post and give you the link.

Other's here seem to like this one, though it's about $30. Still cheaper than a locksmith or dealership route.

https://www.amazon.com/OHP-ELMconfig-compatible-interface-diagnostics/dp/B01F0GVBWY