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Anyone with pats knowledge please help


cp2295

Well-Known Member
Joined
Jul 25, 2013
Messages
1,027
City
Washougal, wa
Vehicle Year
1999
Transmission
Manual
My credo
If you ain't first you're last
So I swapped in the 4.0.. Problem is it won't crank at all, I used the 3.0s battery harness and all the grounds have been hooked into the block. I know the harness' ground locations are different between the two (3.0 & 4.0) but they have the same number of grounds so I don't think that is an issue. I also know they both have the same starter solenoid.

I have my clutch interlock switch bypassed (maybe I did that wrong)

My theft is blinking rapidly with the key in the ignition. I thought it would crank though, just not send fuel.

Is my truck not cranking because of the pats or because something else?

I also plugged in my 3.0s computer into the 4.0 wire harness just to see if the theft would turn off which it did and still no crank (I unplugged the ignition coil and turned the fuel off just to be safe)
 
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My 02 explorer, if I get the fast flashing light (no pats match) it won't crank and what you describes sounds like it is not cranking because of pats.
 
Alright so I just did a little experiment and I took my 3.0s wire harness and computer and plugged it into that big square plugin on the drivers side of the intake manifold and cranked it and it cranked so what would that tell me?

1) the 4.0s wire harness doesn't work with the 3.0s computer as far as cranking it goes (but the theft light turns off so I don't know)
2) the fuse box and that whole wire harness needs to be replaced with a 4.0s?

Because that part of the wire harness (the big square one on the intake) plugs Into the 4.0s engine harness, but maybe even though it does it's missing something and so it won't work? Maybe I'm missing a fuse in that power distribution box??

I thought in this swap you only had to swap engine/transmission harness's, not the other part where it connects to the fuse box and all that other stuff, so if someone could clarify that would be great!

If someone has done a 3.0 to 4.0 swap in the 98-2000 era and can guide me on this part that would be definitely helpful..

Thanks!
 
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My 02 explorer, if I get the fast flashing light (no pats match) it won't crank and what you describes sounds like it is not cranking because of pats.

Good to know.. I'm really really Hoping it's just the pats because swapping the fuse box and all would be a PITA! Not to mention good amount of money..
 
Called ford and he said I need the pats and instrument cluster programmed to the PCM. $185, is he BSing me or does the instrument cluster thing sound right?
 
can you get the key and ignition switch that went with that computer? if so then you can get it to start. really you just need the key and keep it next to the ignition switch and it should fire up. you dont have to reprogram the cluster. if you tow it to ford they should be able to re program the ecm for your 3.0 key. and that seems around the ball park price for it.
 
Yeah at the junkyard I got the PCM at I couldn't get the key and the ignition was gone. My only concern is that with the 3.0s wire harness and PCM plugged in the motor would crank. With the 4.0s harness and and the 3.0s computer plugged in it wouldn't turn over but the theft light was no longer blinking. With the 4.0s PCM and harness plugged in the theft light blinked and no turning over.. That's what makes me think the cluster needs reprogramming but I've never heard of that.

I think I'm gonna ask them to program the key first and then if that doesn't work then program the instrument cluster.
 
Performed another test scenario. 3.0s engine harness plugged into 4.0s PCM. That makes the motor crank. I'm thinking it's in the 4.0s engine harness or something. Theft light does blink, maybe this 4.0s engine harness is bad or I gotta change the fuse box?
 
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The only thing making me not think it's the 4.0s engine harness is because I have a little computer scanner and it hooks up to the 4.0s computer with the 4.0s harness plugged in and it shows the throttle changing and shows the coolant temp and Iat
 
I can't help much more than I originally said. That and some tricks how to convert it so a non-chip key will work but that requires a chip key, or just the chip to do.

You mentioned $180 from the dealer. My concern if you did that with the mix and match hardware that they end up charging money and then blame you for problems.

The only other experience I have to offer is that there are companies offering aftermarket chip keys. They suggest that with a minimum of two keys that one can re-program the PATS to accept the keys. That by entering a code in the keyless entry (don't know if you have that" it can reset the pats into the accept mode. I really didn't look at it all, but I don't know if that would even be viable in that situation. I just came across the info looking for keys.
 
its a 99...both? there are several systems though i dont remember the specifics.




both auto or manual? or one and another?


sounds like you need to move a pin in the 4.0 for crank signal. find the crank wire in the 3.0 harness and block and see if its different from the 4.0....maybe just move it over...i have seen running changes consistently so i would not rule it out.

i dont have the schems in front of me to know one or the other...just seen weird shit consistently especially with 4.0's. even the engines themselves were upgraded continually... i only do swaps with complete matched systems because of that.
 
The 4.0 is a 98, they are both manuals. The 3.0 is a 99. I looked up and down where the big square connector plugs in and I noticed one missing on the 4.0s engine harness compared to the 3.0s, but then I noticed some extra ones.. How do I move a pin and how do I know which is a crank wire?

I got the 4.0 with an auto tranny wire harness, guy I bought it from said it's a 98 and the block and head stamps show that.

At the junkyard I found a 98 4.0 manual tranny ranger so I took it's PCM, and tranny harness not the engine harness, I'm thinking about going back and grabbing the engine harness off that one, and hoping it works.. And hoping it's still there. There was some wires cut I noticed but I'm sure I can splice stuff from the autos wire harness.

Does this seem right? I thought this swap was gonna to be a lot more direct than it is. Really starting to piss me off!
 
I was also thinking maybe the battery cable harness could be at fault since it plugs into the starter. And between the 3.0 and 4.0 they may be different?
 
Or maybe I should find a 99 4.0 engine wiring harness? Does it matter between ranger and explorer?
 
I also just noticed the ranger has system type b pats in 99-00. I read fords pats diagnostic service tips and it said nothing about 98 year ranger. Is this causing my issue since 98 didn't have pats maybe?
 

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