I just got done installing a sohc motor in my 98 ranger & i can get it to run with the ohv computer but not all that great. I have the pats transceiver out of the donor vehicle (2002 explorer) but i have a few questions
1. Does the 02 explorer have a separate pats module that i need besides just the transceiver ring? If so i cannot find it anywhere in the explorer?
2. Can anyone plz tell me where i can get the tx (transmit) & rx (receive) signal from on my 98 ranger or the sohc harness? At the moment i found a gray/orange receive? wire under the column right where the transceiver would have been plugged in if the ranger had pats, i also have tried a few diff white with green strip wires (transmit?) i have found but cannot get my ranger to start with the sohc computer? Also my ranger doesnt have the theft light on the cluster to be able to check if i have it wired right? Ive been looking online for about 4 or 5 days straight now trying to figure out the wiring for the pats system or how to wire it to a non pats ranger & although ive found a few things about just that i cannot find anything that can tell me where i can get the tx & rx signals?
3. Do i need the column from the explorer? In searching for wiring help i keep seeing posts about ppl needing to use the explorer column but nothing that says why or that i absolutely need to?
4. Can i use my ohv computer without to many issues & without any check engine lights? I live in northern California & the smog laws are pretty stricked any cel is an automatic fail
5. Last one i promise! After 3 days of thinking the pats was why my fuel pump wasnt working i finally pulled the bed off last nite & ran direct power to the pump & it was no good & the only replacement pumps i could find around town were just the motor & some seals kinda like a rebuild kit i guess but my gas gauge is stuck at full it was before the new pump & still is i hooked my ohm meter to it & it didnt show anything when i moved the float arm? Im assuming the sender to the gauge is bad is ther any way to clean it or replace just that i already spent 100 bucks on the new pump motor & a new strainer i dont want to have to order a whole new assembly just for that? Also i tryed the cluster out of the explorer & it does the same thing goes straight to full ive checked all the connections between the pump & the relay & all looks good & as far as i can find all the grounds are intact? Srry for the long post & crappy grammar/punctuation ive been working on this thing day & night for 6/7 days & i really need some help & i will be very grateful for any advice i can get thank u!

 

You're going to need to use a SOHC PCM on the SOHC motor. The calibrations would be too different. You're going to want to use the right year PCM for the motor too.

Rather than try to wire PATS up, why not just delete it in the new PCM? It would make your life much simpler. [I suppose it would help here if I mentioned that I can do that professionally]. The Tx and Rx signals come from the transceiver ring module, which snaps around the lock cylinder and reads the PATS key's signal. The transceiver sends and receives data to the PATS module. The PATS module location varied over the years, and I'm no expert on which year Ranger had it where. But it could have been a separate PATS module, or the module could be located in the instrument cluster, or the module could just be built into the PCM. Looking on a diagram to see where the Tx and Rx wires go will show you exactly where your PATS module lives.

Some PATS modules also become the ground for the starter relay, if that PATS system is designed to interrupt the starter. If deleting PATS, you may need to ground this wire.

On the fuel level sending unit, find the two wires at a connector near the tank, and unplug the connector. With key on, fuel level should go all the way up. If you jumper those 2 wires together, fuel level should go all the way down. This is a dampened signal, so it moves slowly. It could move very slowly in the down direction.

 

2002 Explorer had Type E PATS so no module, PATS is in the Computer(PCM), just had 2 wires connected to transceiver(ring)

And yes, it can be deleted by a programmer as Pointisteve suggested

On the PCM pins 17 and 18 are the Rx and Tx for Transceiver
Should be a Grey/orange(17) wire and white/light green(18) wire on those pins

They run to Transceiver, unfortunately you NEED the vehicles connector for the transceiver's connector to match wires, you need the connector from a 2002 explorer
Transceiver comes as a pre-wired unit with a 4 pin connector, unnumbered, with 4 generic wire colors.

2 of the 4 wires are for key on power and ground
Other 2 are for Rx and Tx to PCM pins 17 and 18

If you get the connector from the 2002 explorer it will have correct wire colors to match up, a 2001 to 2003 Ranger connector will have same wiring

Pin 30 on the PCM, should be dark blue/green wire, is the THEFT light activation wire, it is a GROUND when active, so if you want a THEFT light, then get a 12v LED and hook it up to full time 12v power, then hook its other side to pin 30 wire, LED will flash ever 10 seconds or so with key OFF, and then go off with key on it PATS works, if it didn't then LED will flash rapidly and after 60 seconds it will flash a code


No you can't use the 4.0l OHV computer, you will burn the 4.0l SOHC engine up, melt the pistons
4.0l SOHC runs 9.7:1 compression, so needs a knock sensor to run 87 or 89 octane gasoline, even 91 octane might be dicey

4.0l OHV ran 9.0:1 compression, so ran great on any octane


Fuel gauge on/above full means no connection to or in the sender in the tank, the Yellow wire is the wire that runs from the tank to the gauge, with key on if you ground the yellow wire, gauge should go to empty, unground it and gauge goes to full
If that happens then yellow wire is OK, the sender is the issue.
The Black/yellow stripe wire at the tank is the ground for the sender, if you hook that to the yellow wire and gauge drops down the black/yellow wire is also OK

In the old days you could take fuel sender apart and clean it, haven't tried doing that to newer one, but if its broke now what can you hurt?

 

Rond your are the man & i very much appreciate all the help i got the ranger goen last nite & its running great but now i have a new problem. Im getting a p0791 code for intermediate shaft speed sensor & im not sure my 98 transmission has that sensor i definitely have an extra plug on the sohc harness for the transmission im assuming that is what the plug is for & from what i can see there isnt a place in the trans for one has anyone else had this issue & or do u know what i can do to fix this besides i guess getting a 4wd trans from a newer sohc 4.0 ranger /explorer. Or possibly find someone who can tune the computer to eliminate that sensor if thats even possible? Or i know either u or someone else on here when i first started my swap said that the trannys were the same but surely there is a diff between the 2wd & 4wd or would it be possible for me to use the 2wd trans out of the explorer? Thanks again

 

That could be a problem. The PCM and harness need to be a match to the trans electronics. Maybe an older PCM/harness would control a newer trans, but a newer PCM/harness likely won't be able to control an older trans that's not got that sensor.

 

Actually the '98 should have that sensor, 1999 and up they dropped it because it didn't work, the tone ring it was suppose to read kept slipping

Picture of sensor location here: http://www.atraonline.com/gears/1999...gmar99p49a.jpg
The one that says discontinued in 1999

You just need to cut the connector off, strip the ends and twist the 2 wires together then seal the connection(water proof it)
The code is because the wires are disconnected, the 2002 trans wiring probably had that "modification", lol