1998 5.0 XLT Electrical Gremlins. PATs and horn problem.

[CDW6212R]

I hope it gets warmer than freezing for you soon. I don't move well in warm weather, cold is bad.

I'd cut out all non stock wires, as long as you know there isn't any add on device that you need them for. Restoring the sealed condition of the OEM wires would be the best plan, so you don't have to worry about them.

 

[Nate_V8]

All done. Cut the stupid box out and all associated parts. I think I cut out something for electric brakes too.

Unfortunately...........................

Plugged in the used PATS transceiver ring I got from ebay and same problem. When I first tried to start it, I knew it didn't work before the theft light started blinking fast. If the check engine light doesn't turn on when you turn the key on before starting it, it won't start and when you try, it just cranks over and over with the theft light blinking fast.

However I tried turning it off and on several times and all of a sudden the check engine light comes on and I could start it. Tried it several more times and was able to start each time. Then there was 5 or 6 times it wouldn't and then it was fine again. What are the chances I got one with same problem as the one it replaced??

I also now have a new problem...Gah!
My power locks are all screwed up. I push the power lock on the door and nothing, when I use the key fob lock button I can hear clicking at the doors and I can hear clicking from OUTSIDE the truck where the RAP module is, just above the driver side rear wheel. Unlock will unlock the drivers door but that is it with the key fob or door unlock. What the hell is going on?

 

[CDW6212R]

It's possible the wiring removed included something attached to the door locks, and it's severed something of the original lock wiring. I'd begin by checking(swapping around) the door lock relays, those in the rear quarter.

That start issue sounds more like what mine did, just randomly not start etc. How sure are you that the key is a trusted original etc? I'd try the other two keys you should have, see if those work any differently.

 

[boominXplorer]

Did you replace that swapped relay for the horn that was bad? I'd check the other relays in the box by swapping them around.

 

[Nate_V8]

It's possible the wiring removed included something attached to the door locks, and it's severed something of the original lock wiring. I'd begin by checking(swapping around) the door lock relays, those in the rear quarter.

That start issue sounds more like what mine did, just randomly not start etc. How sure are you that the key is a trusted original etc? I'd try the other two keys you should have, see if those work any differently.

Well the only wires that I had no clue what they attached to are the the 2 thin black wires passing through the rubber membrane (I can't recall what is called lol) in the firewall that go into the engine bay. I doubt they had something to do with the door lock wiring. Everything else I found and taped off with no issues.

I am not sure they are original as the keys do not work for the hatch and I did see on ebay tonight that you can buy an ignition cylinder, 2 keys and 2 front door lock cyclinders.. but no trunk lock cylinder. Maybe they were replaced and not the trunk latch?
But the pats problem does the same thing for both keys. What are the chances both could go bad at the same time?

Can you buy new transceiver modules from ford?

Did you replace that swapped relay for the horn that was bad? I'd check the other relays in the box by swapping them around.

I swapped the relays for the horn in the engine bay and when the horn worked I swapped it back. From the look of the diagram online there is nothing close to the horn relay that I could have switched that controls the door locks. They are partly working though, so if a relay or fuse was toast they wouldn't work at all right?



Clicking from the RAP module has me stumped. Maybe it has something to do with being unhooked from the battery so long? (2 weeks).

 

[CDW6212R]

There is a separate relay for the other locks besides the driver's door. The door lock main wires in the LF door are prone to having a break in one of them, two of my three trucks have that problem. So the lock issue might be a wire in the door jamb area cut, or a relay, or some alteration someone did before that is causing an issue.

The PATS is more difficult to diagnose. After the simple things we've tried, it could be time to look at the shop manual diagnostics section, for the PATS. You do need to have at least three good keys, because if you lose one, then you have to pay for a special tool to be used to wipe the codes out of the PATS module. I'd buy another key or two now and see if you can add the codes yourself, if the two old keys will work when you try the programming. New keys on eBay etc, are/were only about $10 last I looked.

The rear hatch key cylinder is an odd complicated part, it has a couple extra latch pieces to it. So that can be bought I think(I got one about 10 years ago($65)), but the hard part is R&Ring the thing. I believe any key cylinder can be altered by a locksmith to work with any key you have. They change the tiny tumblers inside, here it used to be about $40 to come to you and work on the vehicle.

 

[Nate_V8]

Does the RAP module have anything to do with the PATS system?

Concerning the door locks
On the inside of the frame, between the fusebox and drivers door, there was a white wire from the box I cut out spliced into a green wire in which was taped over (the tape was intact so it shouldn't be a problem). I couldn't get to it so without removing the emergency brake pedal system so I cut the white wire and taped it off and stuffed it in there. I could see a bundle of other wires in there, looked to be the bundle that travels under the floor along the door jams on the driver side.
I doubt though that one green wires is stopping ALL the locks as the wire has another spliced into it, it's not cut or broken.

It is possible I just got a transceiver ring with the same problem, it is old and used and is a common issue. The only way to know is to get my hands on a new one.... I hope ford still makes them. I haven't found anyone so far that wasn't able to fix the issue with a new transceiver ring. Maybe it's a ground issue? It's weird that it works sometimes. Maybe I can check the connections where it plug and plays, see if any pins are even slightly pushed out.

 

[koda2000]

i could be wrong, but I don't think the RAP module has anything to do with PATS. It has more to do with key-less entry.

 

[Nate_V8]

Ok I was just checking.

 

[Nate_V8]

I've been thinking over it and I'm going to try something with the PATs ring. It doesn't make any sense that it works sometimes and other times it doesn't. Even if I hold the ring up to the key it doesn't work sometimes yet all of a sudden it will work several times being fixed in place. It did this with the original and the used one I just got off ebay. I've been combing as many threads as possible on this and I found one who had the same problem and it ended up that someone before him cut off the plugs and spliced the wires directly together and added an extra ground. The extra ground was falling off and when he fixed the extra ground it was fine.

I'm going to try pumping some dialectic grease into the plugs and see what happens, maybe even try splicing an extra ground into the original tranceiver ring. I thought it stopped working all together since I removed it because I held it up to the key ONCE and it didn't work so I assumed it was dead (this worked the first time I did this). But the used one I got off ebay did the same thing (didn't work) even when I held it up to key but I kept turning the key off and on and then it worked all of a sudden. Just like the original, just al of a sudden it would work and would work a few times and then nothing for a few times. Again I don't need to start the truck to know if it got the signal, as long as the check engine light comes on when I turn the key on, that means it will start. No check engine, no start, theft flashes quick when I try to crank it.

I'm really thinking it might be a connection/bad ground. As an electronic device, it should work or not work but a sketchy connection can cause this problem, especially a sketchy ground..

Unless I'm completely wrong haha.

 

[koda2000]

Well, over the years I've learned that bad grounds can cause all kinds of weird stuff. I'd just try splicing in a good ground to the existing ground wire and see if that makes a difference. What about the other wire(s)? There could be a break/bad connection there too.

BTW - Twist splices and electrical tape are not a repair. If you don't have a soldering iron, get one. Also pick up a wire stripper, some silver solder, soldering flux, some heat-shrink and do proper repairs. About the only repair I'll make w/out soldering is to use a butt connector and I don't trust those kinds of repairs either. That's a real rat's nest of wires you've got there.

 

[Nate_V8]

It would have to be a bad connection because if it was a break it wouldn't work at all. I will check the others but for some reason I feel like a bad ground is the problem (if a poor connection is the problem).

I know twist splices and tape are not repairs. I have a picture from years ago when one of the mustangs I had almost caught fire due to **** wiring. Turned out the PO used green wire for EVERYTHING and just twisted and taped everything together. Green for positive AND negative. Good times....

As for what I've done so far, the wires I sealed up with tape were just exposed wire with no danger of arcing or grounding out on anything. There is nothing I had to splice back together. For the most part, most of the wires (save 3/6 ignition wires) were soldered at least but no shrink wrap, just tape.

I will have to look at the wring diagram for the locks/rap module if I can't see a broken wire or anything that is clearly the problem. My only concern is since the locks partly work, how would it be a broken wire for the locks?

 

[CDW6212R]

Good thought, a poor connection can do all of that. Keep an eye out for any other things which someone else might have worked on. Dash wiring is great and rarely has faults, but like an engine harness, old age and becoming brittle, handling any of the wiring can create an issue. You hate to have to work on old wiring, but also you want to avoid anything someone else might have messed with.

I bought a dash harness from a 2002 Mustang, but not the first one I found, because it had had a remote starter installed in it. I didn't want that harness, in case any connections that were made damaged the original wiring. That was for my 92 Mark VII, which this year I hope to rewire with that 01/02 Mustang wiring, including a 97 Explorer engine/trans harness, to make it OBDII etc. I've got lots of wires in boxes, a big puzzle with way more pieces than a boxed puzzle.

 

[koda2000]

Sometimes you can have a wire with broken strands under the insulation. A wire like that may only carry 1/2 the amps of whatever gauge the wire is rated for. That may cause a device to work, but work poorly. You can also have wires that are completely broken under the insulation. These broke wires, if disturbed, may carry current sometimes, but not at other times.

I was once working on an acquaintances classic car. He had recently paid someone $1500 to "rewire" the entire vehicle, but had a host of problems afterwards.

An example of three of his problems were:
- Driver's power window worked, but very slowly.
- Brake light only on one side, only tail light on the other side.
- The in-dash ignition switch got so hot you couldn't touch it.

The driver's power window issue was because the person that rewired the car used about six 8" pieces of different colored, different gauge wire scraps, butt spliced together, to carry the power to the window motor. The window motor was only receiving 7 volts due to all the resistance.

Brake/tail lights were never rewired and there were broken/bare original wires running across the trunk floor.

The HOT ignition switch was my favorite. The person had re-wired the ignition switch with more wire scraps and butt connectors, but apparently didn't have a crimp connector large enough for the primary wire coming from the battery, so he just twisted it loosely around a stud on the ignition switch. The poor connection carrying a lot of amps got really hot. So hot that it heated up the metal ignition switch. If the dash wasn't 100% metal it would have melted. If that wire ever fell off the stud and grounded out the whole car would have probably caught on fire.

When I told my acquaintance what I found (and fixed) and that he had been ripped off because he'd paid someone $1500 to ruin his car he got mad at me. I offered to actually rewire the entire vehicle correctly using a Painless Wire kit, but he just ended up selling it to some other sucker.

 

[mic98xlt]

To me, erratic electrical problems such as yours indicates a bad ground. Bad grounds cause all kinds of crazy problems because they are essential points for reference in a 12 volt system. This would explain why sometimes the gremlins disappear and other times reappear again. The grounding points are often taken for granted to be good and valid, leading to a bad assumption and leading you down the wrong trouble shooting path.

I once helped a friend chase a electrical problem with his head lights and other lights appearing dim. The ground between the body chassis and the negative battery post were eliminated by mistake during the engine swap. We chased that once for weeks before we realized that a solid ground strap was needed between the front metal header panel and the negative battery post.

On these Explorers second generation, often on the firewall by the PCM, the grounding spot is only good at one dedicated metal post point. During a engine swap it is often removed, but often replaced back on the first available metal nut that someone finds. Other firewall grounding points are at best a partial bad grounding point. When this was done on my Sport, most of the dash instruments worked fine but the fan switch and blower didn't. This is just food for thought while you are troubleshooting.

 

[CDW6212R]

Good thoughts. Check the easy to get at main ground points. The big battery and alternator wires you can check fast. Hunt the many other grounds, which I think all have green 8mm head bolts going into the chassis. There's one main bolt on the radiator support near the battery and radiator cap. Check the one in each kick panel area, very close to the bottom front edge of the dash. That left one I hope doesn't have several added wires on it. There's one in the LR quarter panel area, near the relay box that has the door lock relays in it. Most circuits in some way ground through those main grounds, plus the one on the firewall from the engine. The whole chassis is a ground path for almost all of the circuits.

 

[koda2000]

Good thoughts. Check the easy to get at main ground points. The big battery and alternator wires you can check fast. Hunt the many other grounds, which I think all have green 8mm head bolts going into the chassis. There's one main bolt on the radiator support near the battery and radiator cap. Check the one in each kick panel area, very close to the bottom front edge of the dash. That left one I hope doesn't have several added wires on it. There's one in the LR quarter panel area, near the relay box that has the door lock relays in it. Most circuits in some way ground through those main grounds, plus the one on the firewall from the engine. The whole chassis is a ground path for almost all of the circuits.

There are also 2 braided ground wires on each side of the frame that go to the body. These braided ground wires often corrode on rust belt trucks. You can find replacements in the HELP section of most auto parts stores.

 

[Nate_V8]

So some interesting developments.

I tried the original pats transceiver ring and as I thought it still works. Here's the weird thing though. I plug in the original, try it and nothing. So I read about leaving the key on with the theft light flashing for 60s and then the theft light will blink in a pattern. The pattern was 1:6 which is faulty link between PATS module and EECV.

Here is the interesting part. While waiting the 60s with the key on and theft light flashing fast, my check engine light comes on and I hear the fuel pump prime. OK what? I already know that means I can start the truck and after getting the code pattern after 60s I tried starting it and it started right up. What the hell??? No idea how that works.

I then unplugged the battery and tried following the wiring and the wires go up inside the dash toward the center and I couldn't see any ground. I looked around for other grounds and took off panels, everything looked fine unfortunately lol. So I sprayed some sensor clean on the PATS transceiver plug, plugged it back in and pushed all the wires in toward to connectors and some wires did move, I'm not sure if it did anything but it was able to start every time after that and that is at different intervals. I'm not assuming I fixed it though.

As for the locks. I tore apart the floor along the doors where the wires run to the RAP module. Everything looked fine and intact. So I look at the drivers door and there is a weird black plastic cylinder with a nut on it that has the door wires coming from it. So I start undoing the nut and was expecting the top to come off. instead it drops the bottom out. So instead of inspecting it I put it back and tighten it back up. Now all my locks work. Perfect! So I go and disconnect the battery and unplug the PATS tranceiver module as it was temporarily placed, plug the battery back in. No more locks. Same thing as before, drivers door unlock button and key fob unlock will only unlock the drivers door, nothing else works. So I take apart the cylinder at the door again, look at it, see one of the female connectors is out of whack, spray some sensor clean in and install it again and no locks. Sun was fading by that point and my hands were starting to freeze so packed it up for the day.
So guess the problem lies within that cylinder? I pulled off the rubber boot and I didn't see broken wires and would be odd that the ones inside the door would be broken. The bent female connector could have been when I took it off the first time. It still doesn't make any sense why they would stop working within the 2 weeks the truck has been sitting there unplugged.

This looks like it would cost me a small fortune to fix. What a piss off, this is getting old quick

 

[koda2000]

Intermittent PATS issue - Seems like your zeroing in on a bad connection to the transceiver ring.

Hearing fuel pump prime - PATS does not disable the fuel pump. It's turns off the fuel injectors.

Door locks - It sounds like you have a broken wire(s) in the wire bundle going from the driver's door to the cabin. This is very common. By messing with the barrel connector you probably made temporary contact which allowed the locks to work. After opening/closing the driver's door a few times, contact was once again lost. The wires leading from the driver's door to the cabin often break due to the multiple tens of thousands of times the driver's door is opened and closed. Remember we're talking about a 20 year old vehicle here.

- Undue the bolt on the top of the barrel connector until the bottom drops out.
- With a helper, remove the four 13 mm bolts that hold the drivers door hinges on and remove it.
- Cut off the wire-tie that holds the rubber boot on the lower part of the barrel connector and pull it back. Carefully check all the wires found under the boot for breaks (external and internal). Fix any broken wires found. I'm pretty sure the wires that control door locking/unlocking are pink/yellow and pink/green, but consult a wiring diagram.

Free wiring diagrams can be found at the following link in the Auto Repair Reference Center.

EBSCOhost Login

USERID = s8921298
PASSWORD = password

 

[Nate_V8]

Hearing fuel pump prime - PATS does not disable the fuel pump. It's turns off the fuel injectors.

Door locks - It sounds like you have a broken wire(s) in the wire bundle going from the driver's door to the cabin. This is very common. By messing with the barrel connector you probably made temporary contact which allowed the locks to work. After opening/closing the driver's door a few times, contact was once again lost. The wires leading from the driver's door to the cabin often break due to the multiple thousands of times the driver's door is opened and closed. Remember we're talking about a 20 year old vehicle here.

- Undue the bolt on the top of the barrel connector until the bottom drops out.
- With a helper, remove the four 13 mm bolts that hold the drivers door hinges on and remove it.
- Cut off the wire-tie that holds the rubber boot on the lower part of the barrel connector and pull it back. Carefully check all the wires found under the boot for breaks (external and internal). Fix any broken wires found. I'm pretty sure the wires that control door locking/unlocking are pink/yellow and pink/green, but consult a wiring diagram.

Free wiring diagrams can be found at the following link in the Auto Repair Reference Center.

EBSCOhost Login

USERID = s8921298
PASSWORD = password

I know the PATS disables the injectors which is why I find it weird. Maybe I'm actually hearing something prime in the front? Something primes! I'm still lost as to why it started up 30s in with the theft light flashing fast. Theft continued to flash in pattern when I started it up too.

I will add that when the door locks all started working it was when I had all the plastic floor molding off revealing the wire harness track along the floor, I don't know if that matters. When I unplugged that barrel connector the first time and plugged it back in and the locks started working; I unplugged the battery and reinstalled the PATS transceiver, ****put all the floor molding back*** and plugged the battery back in only to discover no locks again. even with removing the boot and inspecting the wires and spraying in cleaner and trying to reattach it twice.

I found a thread with people having close to similar problems. I haven't tried the rear power lock yet but looks like everyone has a problem with some pink wires on the floor. I'm wondering if it was coincidence that my locks starting working after I removed that cylinder as beforehand I removed the floor molding. Maybe I moved something on the floor wiring harness? I can't recall exactly but I'm pretty sure I didn't try the lock after removing the floor molding and only tried after unplugging and plugging in that barrel connector

I did cut the zip tie and pulled the boot back but maybe I didn't look thorough enough. I will inspect the floor harness again tonight and check the rear power lock. Going to be hard to get a helper and find time to remove the door.