Failure to Communicate with PCM while trying to program key

[Brain75]

my bet, if it is at all similar to the one I took out, it is under the drivers side kick panel, and there will be one wire (mine was green, but that doesn't mean anything) that snakes out into the engine bay and goes off towards the horn... I would start on that side and hunt down the horn wire, then work backwards... if you really really just can't find the horn wire under the hood then they might have dug around in the dash to find it (it is really buried in a big group of cables at that point though, so would have been a PITA for the guy before you to put in)

 

[zf98ranger]

my bet, if it is at all similar to the one I took out, it is under the drivers side kick panel, and there will be one wire (mine was green, but that doesn't mean anything) that snakes out into the engine bay and goes off towards the horn... I would start on that side and hunt down the horn wire, then work backwards... if you really really just can't find the horn wire under the hood then they might have dug around in the dash to find it (it is really buried in a big group of cables at that point though, so would have been a PITA for the guy before you to put in)

Okay, I pulled off the kick panel and will hunt for that next!

 

[zf98ranger]

To update:

I pulled out the fuse for the horn relay so that I can work in peace and stop pissing my neighbors off. Once I did that, I waited a period of time and tried to start the truck. It worked! I also tried the 8 turns in ignition thing, and that also worked to put the truck into programming mode. The locks cycle and all, but i dont have a fob so i dont think it matters. The door chime is still going off anytime the drivers door is open and the key is out of the truck, but the hazards have stopped and there's no clicking at the horn relay, so maybe just a door chime issue.

So maybe this is not a PATS truck after all? It has the Theft light, but this unprogrammed key is getting the engine to start. However, the most important thing: the truck now cranks, starts, and i can rev the engine and see my RPM gauge react, but it won't go forward or reverse. It feels like the parking brake is on (its not, the release lever is working). No wheel spin. Could this be related to an aftermarket theft system still partially activating, or is this a transmission issue? The truck was running when I lost the key a week and a half ago, but it wouldn't be the most surprising thing in the world if something was bad with the transmission.

 

[Brain75]

does the horn sound 100% of the time like there is a frozen switch or short? or does the horn sound, pause, sound, pause - the typical of just about every alarm out there?
Based on your answer to those I would give ya the direction to hunt on that issue....


Based on the fact it starts and runs without a chip key, just a regular ole dumb key I would say you certainly don't have PATS...


soo.... when you pulled into the drive 1 1/2 weeks ago, everything normal, brakes weren't catching or nothing it came home all normal?
Sounds mechanical, like frozen brakes, hung up parking brake, trans issue, but I can't think of anything that would cause that while sitting...or you would have noticed in the last mile coming home...
I'd lift the rear up with jack stands put it in neutral and try to spin both wheels - simplest check of the drivetrain from the output shaft backwards...

These are the RKE FOBS that I bought and programmed in with page 166 something of the owners manual:

Strattec 5925871 Keyless Remote Key for Strattec 3 Button

High Quality Ford Keyless Entry Remote Key 3 Button Strattec 5925871

www.key4.com

 

[Brain75]

1998 appears to have a much shorter manual - page 34 for your vintage:

https://www.therangerstation.com/resources/manuals/1998_ford_ranger_owners_manual.pdf

 

[zf98ranger]

does the horn sound 100% of the time like there is a frozen switch or short? or does the horn sound, pause, sound, pause - the typical of just about every alarm out there?
Based on your answer to those I would give ya the direction to hunt on that issue....


Based on the fact it starts and runs without a chip key, just a regular ole dumb key I would say you certainly don't have PATS...


soo.... when you pulled into the drive 1 1/2 weeks ago, everything normal, brakes weren't catching or nothing it came home all normal?
Sounds mechanical, like frozen brakes, hung up parking brake, trans issue, but I can't think of anything that would cause that while sitting...or you would have noticed in the last mile coming home...
I'd lift the rear up with jack stands put it in neutral and try to spin both wheels - simplest check of the drivetrain from the output shaft backwards...

These are the RKE FOBS that I bought and programmed in with page 166 something of the owners manual:

Strattec 5925871 Keyless Remote Key for Strattec 3 Button

High Quality Ford Keyless Entry Remote Key 3 Button Strattec 5925871

www.key4.com

The horn was going off and pausing at short intervals, very much like your average alarm. I'm now convinced that the locksmith had set off a non-PATS alarm system (still looking, so I'm not sure whether its factory or aftermarket), then tried to program keys since the dumb keys wouldn't work, but the dumb keys would have worked if we'd just waited and reset the alarm in the analog pre-PATS sense. Now that I've done that, the truck is starting on command with the chipped but unprogrammed key.

Regarding the truck's state when the key was lost, it seemed fine! I was fishing, unloaded my kayak, put everything inside, and lost the key who knows where in the meantime. It didn't seem to have any braking issues, transmission has fluid in it that doesn't look burnt or anything. If I jack it up and the wheels do or do not turn, what would you say the next move would be? As it sounds, if it's a transmission, there's not much I can do other than have it towed, but if the brakes are frozen for whatever reason, I could remove the wheels and lightly pound them with something to break them loose, correct? The parking brake is disengaged in the cab, at least it seems that way, but if I jack it I'll also check the cables.

 

[Brain75]

Sounds like the either the panic (of the RKE) got set off... page 30 something - a few ahead or behind of page 34 said there was a panic feature....or back to the aftermarket.... but the manual says the panic will go off entirely if you either press the button (on a remote you don't have) or turn the ignition to ON or ACC.

Since you got the ignition cylinder to ON already, would ask - horn still sounding?

If the trans is in neutral, only half the trans is spinning so the effort is minimal, all you are turning is the driveshaft, wheels, axle and output shaft +/-. If the trans is in any gear you are trying to turn the engine too, very very hard unless it is shot and has no compression.

 

[zf98ranger]

Sounds like the either the panic (of the RKE) got set off... page 30 something - a few ahead or behind of page 34 said there was a panic feature....or back to the aftermarket.... but the manual says the panic will go off entirely if you either press the button (on a remote you don't have) or turn the ignition to ON or ACC.

Since you got the ignition cylinder to ON already, would ask - horn still sounding?

If the trans is in neutral, only half the trans is spinning so the effort is minimal, all you are turning is the driveshaft, wheels, axle and output shaft +/-. If the trans is in any gear you are trying to turn the engine too, very very hard unless it is shot and has no compression.

Regarding the horn, it has stopped. I put the fuse for the horn relay back in and checked to see if the horn itself was working and it is. No other indications present that the alarm is going off except for the door chime anytime the door is open and the key isn't engaged. Theft light is off, horn has stopped, hazards aren't on.

When I hit the gas in drive, reverse, or first, the truck lurches forward a bit exactly like it would if the rear brakes were engaged with the parking break. I guess my biggest fear as of now is that there's an aftermarket alarm that I've yet to find that is somehow locking the braking system? Especially because my fuse box under the hood doesn't have fuses for the abs system and the abs module is behind my radio, which im not sure is standard. But I don't know enough about this stuff to know.

 

[Brain75]

Aftermarket alarms usually have an engine ignition kill. I haven't seen any capable of setting brakes. I would guess either
A) the transmission controller is nerfing the trans (from panic or **very unlikely** aftermarket alarm)
B) some mechanical something somewhere completely unrelated - non electrical.

I have not seen an aftermarket alarm that was capable of disabling the trans. But my experience with alarms are the cheaper glassbreak/door open/etc - nothing really really spendy that tied into factory computer.

 

[zf98ranger]

A) the transmission controller is nerfing the trans (from panic or **very unlikely** aftermarket alarm)
B) some mechanical something somewhere completely unrelated - non electrical.

This makes sense to me from where I am. Trying to weigh the pros and cons of continuing to rip up the interior looking for an alarm system when the truck is cranking, starting, and acting like it wants to move.

 

[zf98ranger]

Update: I have successfully removed the rap module from the truck. The horn went off for a bit and then stopped once I finally got the second connector unplugged. However, the truck still won't move! I can feel it shifting gears in the cab and when I hit the gas, it lurches forward or backwards and rocks if i hit it hard enough. Does that do anything to rule out a serious transmission issue and point towards the brakes?

 

[lil_Blue_Ford]

Could be brakes locked up, but with some throttle and rocking it should have broken them free unless they are really bound up, in that case you may need a bunch of new brake stuff…

 

[zf98ranger]

Useless update: I found the original key after about two weeks. So all of this may be for nothing, and I may have bricked my truck for nothing! But even with the original key placed near the ignition/steering column, the truck is starting, but not moving, so it does nothing to solve my problem. For anyone who has read all of this, this is exactly the place I was in when I first lost the key but was able to get the ignition turned and the truck started with my hand. Crank, start, rev, no movement. So it seems that it may be a separate issue, considering it happened both prior to and after the ignition lock cylinder swap.

At that point, the alarm had not even gone off, so it seems unlikely that the alarm system "nerfed" the transmission somehow. It does seem odd, though, to think that I'd have my first serious mechanical issue at the same time that I lose my key for the first time and they just happen to coincide, but it wouldn't be that strange on a thirty year old truck, I guess. At this point, it seems like I'm now back to square one with a mechanical issue related either to the brakes (unlikely) or something to do with the transmission. Hoping it is an easy-ish fix. My next steps will be to check the parking brake cable for some kind of seizure, check transmission fluid, and see if I can get the truck jacked up to check the wheels to see if they move. The truck is on grass and I'm not totally sure I even have a jack that can get it up, but we'll see. There are no check engine lights on or anything, so I had been thinking I could get a scanner, but it doesn't seem like that would help. I am wondering, though, if there's some relationship between the PCM that the locksmith couldn't get a read on and the transmission? Maybe I should check some fuses and a solenoid or something. The problem has turned into a new and potentially worse problem, haha

 

[SenorNoob]

If you feel the truck lurch, the transmission is trying to move it. I'd be looking closely at brakes at this point. If nothing is dragging, it shouldn't be hard to roll the truck in neutral.

It's possible a badly slipping transmission would lurch some but not have enough torque to actually move anything. Hows the fluid level?

 

[Brain75]

gonna grab your question out and post it all by itself so the trans experts can chime in (I am totally a manual guy, I hate the wizard boxes)...

...I am wondering, though, if there's some relationship between the PCM that the locksmith couldn't get a read on and the transmission? ...

My own response to that is: A bad/dying/dead computer can cause hard shift, inappropriate shift, and failure to shift - including not even getting into 1st.... beyond that I can't really advise... I would say if it lurches, then your issue is probably not in the computer...but that is a guess.

All the PATS systems (which you definitely don't have) is around spark kill/starter kill/start but not run more than 1 second - all ignition/start, the PATS system has nothing to do with transmission (yet as of 2025).