Computer

[brianhood]

Got a general question hear about Pats I’m wondering if anybody can help me find the correct solution . I’ve got a 2000 Mazda B3000 and a 2000 Ford Ranger. They both have the automatic transmission with a V6. They are both two-wheel-drive. On paper I think they’re both 100% identical. The Mazda has been rolled over but has a perfect low mileage powertrain in it including the motor and transmission. The motor and transmission in the Ranger is pretty much worn out and smoking and broken with over 300,000 miles on it. I’ll pull the engine and transmission from the Mazda to put into the Ranger. However I seem to have lost the ignition key for the Ranger. Since Both of these trucks seem to be identical, can I simply swap the computer, the Pats box, And will I need to swap the ignition key transponder fob? I do have this complete set up from the Mazda. If you think this will work? Will I have to have the computer reflash or should I just be able to plug it all and then go? Any help with this issue will be appreciated. Thanks Brian.

 

[Dirtman]

2000 is PATS one. The key info is stored in the PATS module, it tells the computer if its cool to start the truck. So the key is only linked to the module and not the actual ECU. If you swap the module and ignition with it's matching keys to the other truck your good to go. Only on PATS 2 (2004+?) Is the ECU actually the part coded to the key, aka no pats module.

I'm like 99% sure on this lol. @RonD is the expert here though.

 

[RonD]

+1 ^^^

Except...........PATS Module and computer are a matched set, so have to be swapped together, they share an RSA encryption Key
2001-2003 had PATS in computer
2004-2011 had PATS module inside HEC digital instrument cluster, so was similar to 1999/2000 with "matched set" separate PATS module, which makes swapping clusters in a 2004 and up a pain in the a$$

Yes, your plan will work
Swap over computer and PATS module together and ignition key cylinder

The transceiver around key is just an antenna not matched to anything so that doesn't need to be changed, in any year

You might check 8th digit in VIN to make sure Mazda computer is not Flex Fuel, which would also need the Fuel sensor moved over
If they both have the same 8th VIN digit then all is well, it will be a "U"(gasoline only) or "V"(Flex fuel)


You can add new keys to existing computer using Forscan software
Take ignition cylinder to lock smith and have him cut 2 new Ford transponder keys to fit lock(it will also fit the doors)
You need minimum of 2 new keys to add them in Forscan, because others are all erased, which is good if you lost a key because it could be used to open doors but not start the engine.

OOPS: forgot you don't have a key to get out the old ignition cylinder, which will be an issue for this swap either way
You need to get Mazda one IN, so have to get the Ranger one OUT
You may need to see what a mobile lock smith would charge to come out and make a key
You could try taking a door lock in to lock smith to get a key made but I think door locks uses 8 pins and ignition 10 pins so key made only from a door lock might not work in ignition to turn it

 

[Dirtman]

See... always good to wait for Ron lol. I didn't think the ECU cared on PATS 1. Just the module.

 

[RonD]

The computer needs the "OK to Start" from PATS module, or no fuel injectors or fuel pump
So they share an RSA encryption key to exchange messages

Not "secret squirrel" stuff because the message content is easy to decrypt with a fast computer but would take a few hours or days depending on decrypt computers speed
So RSA is used for real time messages that have an expire time, common used was for Video/audio scrambling(satellite and cable TV) where the encrypted data was changed every 10-20seconds, so unbreakable in "real time"
Same for this use, the "OK to start" message changes each time its used, at each start up, so capturing the encrypted message for "OK to start" and decoding it wouldn't do you any good because you can't repeat it and match the encryption without the shared RSA Private keys in both units
Its a very simple encryption but unbreakable in real time applications

 

[brianhood]

Thanks guys!

 

[rubydist]

Can't you just eliminate the pats with Forscan if you want?

 

[Dirtman]

Can't you just eliminate the pats with Forscan if you want?

No. Forscan cannot change the software. As far as PATs goes all it can do is program keys. And even doing that is a tad tricky.