Hi Everyone,
I've searched the threads and found various pieces of advice but none seem to exactly fit the bill. I would appreciate any advice someone might have. Here's my situation:
1997 Ranger XLT
Owned vehicle for 7 years, 175,000 miles on it.
2.3L, 5 spd manual, 2 WD
No PATs -- factory anti-theft system (uses horn, with little "Theft" light in lower right of instrument cluster).
Three weeks ago someone tried to steal the truck (why??? It's 25 years old with 175k miles --weird . . . ) by hammering on the key cylinder with a chisel and trying to force it over into the on position and then presumably they would try taking the cylinder out. Fortunately they were not successful getting it into the on position and gave up, but they damaged the key cylinder to the point that it won't rotate into the on position with the key in it. So I bought a replacement Dorman key cylinder and drilled out the little push-button retainer button on the bottom of the damaged cylinder and slid it out. Then I put the new cylinder in (with new key) and got the little gears in the bottom of the cylinder all synced up. So far so good. But when trying to start everything comes on (IP lights, fuel pump, etc.) but the anti-theft system kicks in and it wont' start. The horn starts honking and the red "THEFT" light blinks on the IP. I've now disconnected the horn so I can try to work on it without irritating the neighbors, but I can't seem to get past the system. Based on similar situations I've seen in the threads, below is the advice I've seen and what I've tried

1. Disconnect / reconnect negative battery cable. [Did this, no effect].
2. Disconnect negative cable, put key in on position, reconnect negative cable [Did this, no effect].
3. Close doors, turn key to on position then back to off position -- repeat 8 times, leave in on position on last turn. [Did this, no effect].
4. Ground dark green / purple stripe wire coming from door inside drivers side lower left kick panel [Have NOT tried this -- seemed unreliable in other threads].
5. Disconnect RAP module (not exactly sure where this is) and ground one of the wires (can't remember exactly which one). [Obviously have NOT tried this one].
6. Turn over engine compartment fuse block and snip the white / blue stripe wire coming out of #3 fuse terminal (starter + anti-theft, 20 amp) block, leaving alone the orange/blue (I think) wire also coming out of that terminal as it goes to the starter. [Have NOT tried this -- am afraid of what else that white/blue stripe wire might be feeding -- but the author swore this worked on a very similar problem.]

So, I've done 1-2-3, have not done 4-5-6, but have read about lots of seeming failures with 4-5. Only read one thread mentioning #6.

I'd appreciate any advice anyone may have on this problem.
Thanks,
Mark

 

Welcome to the forum

1997 anti-theft wire diagram below

Its call a RAP module and its behind driver seat and behind the plastic panel, its bolted to rear panel of the cab

System looks more complicated than it is, lol

Drawing of ignition cylinder holder and its "tamper switch" here: https://ww2.justanswer.com/uploads/K...450_tamper.png
I would assume this was damaged and is whats causing the issue

But there is also a switch on driver door(or passenger door) which must be unlocked with a key(or FOB) to disable RAP module(the dark green/purple wire)

Triggered RAP activates horn and park lights and enables starter interrupt relay, so no crank, this relay is the only thing that prevents startup, nothing disables spark or fuel with this system, it has no "kill switch"

Yes behind the kick panel on drivers side or passenger side a Dark Green/Purple wire comes out of the door
If you GROUND this wire then that deactivates RAP, but unlocking either door should do the same thing
i.e. when you lock the doors that activates the "alarm system" while you are away from vehicle, when you unlock the doors it deactivates the alarm system, so YOU can drive the vehicle, lol
So unless both doors lock/unlock switches are damaged I doubt GROUNDING the dark green/purple wire would help

I think you need to have a better look at the Tamper switch, it has two wires, a black ground wire and a dark green/white wire
If this switch is damaged then there is no "reset" possible by unhooking battery, RAP has full time 12v, so as soon as battery is hooked back up, the damaged Tamper switch activates the alarm..........again

Tamper switch can only have two positions, grounded or ungrounded, so if you can't find a replacement switch or just want to see if this is the issue pull off the clamshell on column and find tamper switch connetor
Unhook battery
Unplug switch so no connection, ungrounded
Hook up battery
See if alarm is triggered if not try starting
If alarm is trigger unhook battery
Jumper the two tamper switch wires together, so grounded
Hook battery back up
Alarm should be off now
(if door locks are unlocked and grounded, lol)


You didn't mention if alarm was triggered by the thieves when they were trying to get the lock cylinder out?
If not then was the vehicle unlocked, so RAP was "offline"?
If it was locked then alarm should have activated when door was opened
Did they open the hood?

 

Ron,

Thanks for the reply. Indeed that tamper switch investigation sounds promising. I didn't realize that's what that little thing is. When I took out the damaged cylinder the tamper switch (which appears to have a copper lever that makes contact with the cylinder) just fell out and is currently hanging by the wires (still has the little plastic thing on the end with the copper lever/switch). Based on other conversations, I thought it was related to the door chime that goes off when you open the door so I haven't done much with it except a half-hearted attempt to slide it back into place on the new cylinder. I tested touching the copper lever to the column and not touching to see if it would fix the door chime problem (separate annoying problem). When it seemed to have no effect on the door chime i just left it half-heartedly attached to new cylinder.

But since you say it's a key component of the anti-theft system (now that I know its a "tamper switch") I'll experiment with grounding and ungrounding it and reply with results. Appreciate your time in replying.

--Mark

 

Ron,

I neglected to answer your last 4 questions.

No, the alarm wasn't triggered by the thieves because the doors were unlocked (two reasons for not locking it: first, I figured no one would ever want to steal a 25 year old truck, and second, there are so many vehicle break-ins around here that leaving the doors unlocked often prevents thieves from breaking the window to get in. Just don't leave anything valuable inside. Lovely).

--Mark

 

There is a separate door chime switch, just has one wire, opposite side of cylinder from tamper switch

You can just cut this one wire and no more door open/key in chime
This switch was grounded by the key being inserted in the cylinder, when grounded if door was opened chime would sound
So ungrounded means no chime, make sure wire is not damaged so it can't ground inside the column

I am not sure if tamper switch is grounded or ungrounded in its Untampered "status", lol, but its a switch with TWO wires, so touching it to metal housing wouldn't help one way or the other, the two wires either need to be shorted(together) or Open(not touching)

UPDATE
In the diagram it does look like there is a resistor in the tamper switch, so these two wires may need to be connected WITH a specific resistance to ground, this means wires can't simply be twisted together to bypass switch
I have seen this used on motorcycle ignitions, to prevent hot wiring, i.e. bypassing ignition switch
So disregard earlier suggestions
Have tamper switch plugged in and CLOSE it, use tape or ?? to hold it closed

 

Ron,

Ah-ha, so maybe I DON'T know what the tamper switch actually is -- I might be confusing it with the door chime switch. I'll take a much closer look when I get home and get this sorted out.

--Mark

 

Chime switch is one wire and on steering wheel side of cylinder
Tamper switch is 2 wire and on dash side of cylinder

 

I did find the resistor value for the tamper switch, 162 ± 40 ohms

Its an always closed switch to RAP module that should have 150 to 200 ohms
It won't activate alarm until ignition switch is turn on or to accessory, then if there is more or less than 150 to 200 ohms on that tamper switch wire to RAP the alarm will activate and disable start up
So thieves must have never got to the point of turning key ON, so no alarm went off

So if you can't find a replacement tamper switch(assuming it is damaged) then you can connect a 170 ohm resistor between those two wires and tape it up inside the column
It won't disable alarm just the tamper switch

 

Ron,

Hey, thanks for going the extra mile to look up the resistance for the tamper switch. Unfortunately that switch seems to be ok. I located the switch (thanks to your good directions) and separated the wire at the connector under the column. Here's what I did:

1. Left switch disconnect (ungrounded) and reconnected battery. Result: Theft light blinking -- no start.
2. Stuck jumper wire in the connector between two terminals going back to RAP (grounded). Verified with meter that I had continuity between two posts in terminal (verified jumper wire making contact with both terminals). Reconnected battery. Result: Theft light blinking -- no start.

***Ooops, I just saw your edit that said don't bother with the two items above.

1. Checked resistance across disconnected tamper switch. Result: 161 ohms. Rats -- just about perfect according to your numbers.

Oh, correct -- thief never got the cylinder to the on position. Doors were unlocked and hood was not raised.

I should note that at this point I'm not concerned with maintaining the alarm system, so if you know of a way to fix this at the cost of losing the alarm system -- that would be an acceptable consequence.

Any thoughts on that suggestion of snipping that white / Lt blue wire come out of the starter fuse block under hood?

--Mark

 

Seems like most people are having problems with the PATS on 1998 and later years. Anybody else have problems with the old (non-pats) anti-theft -- and were able to come up with a solution?

--Mark

 

Actually very few have issues with PATS considering Ford used it world wide
But when there is an issue its a PITA, lol

In 1998 V6 Rangers PATS was a "Pay Extra" Option, in 1999 and up V6 Rangers it was Standard feature
4cyl Rangers didn't get PATS until mid 2001 when Rangers got the new 2.3l Duratec engines

Most common issue with PATS is losing the ONLY KEY left, lol, which I wouldn't call a PATS issue, but your still stuck, have a CLONE key made for a spare, its cheap
2nd common issue is low voltage, old battery, PATS resets when starter motor is activated and battery volts drop too low, or just dirty battery terminals/cables
3rd would be transceiver, its a powered antenna and can fail but not expensive or hard to change, no programming required

4th would be user error, if you attempt to start engine with rapid flashing THEFT light 3 or 4 times, PATS locks the system for 90min or so, so even if you replace battery or clean the terminals it will not start within that time, and if you try again, then the 90min "clock" restarts from the last attempt, and timer holds at that point if you disconnect battery
So if timer was at 30min when battery cables were unhooked, then when battery is hooked back up again it starts timer at 30min so another 60min to go, but sometimes it will reset to 90min again
The whole point of an Anti-theft system is to delay a theft if it can't be prevented
Which is why it can take 30+min to program new keys using a laptop



Alarm systems have their own issues, PATS is "Passive" Anti-Theft System, passive, so no horn honking or lights flashing
Alarms primary function is to scare thieves off by making noise and flashing lights to draw attention to the breakin
Some Alarms will have relays that disable starter motor and/or fuel pump
And use sensors to detect intrusion
PATS is pretty straight forward and limited in what can go wrong, not hard to diagnose
Alarms have many more possible failure points

 

Ron,


Any thoughts on that suggestion of snipping that white / Lt blue wire comes out of the starter fuse block under hood?


Also note what I mentioned about ultimate goal:: I should note that at this point I'm not concerned with maintaining the alarm system, so if you know of a way to fix this at the cost of losing the alarm system -- that would be an acceptable consequence.

​​​​​​​
--Mark

 

White/light blue wire at engine fuse box powers the RAP module but ALSO the fuel system/pump

Just unplug RAP module and Ground the light green/purple wire on that connector, that grounds the starter interrupt relay so it always allows starting

 

Ron,

Ok, that's really good info on the engine fuse box wire. Thanks for warning me.

So I'll take your advice on the RAP module -- find it, and ground the wire you describe (and report back). You mentioned that the RAP is behind the driver's seat behind a panel -- I believe on another thread you said it's near the seatbelt anchor point on the floor ?? I have an XLT extended cab (with jump seats) -- can you be more specific on exactly where it is so I don't go pulling off a bunch of extra panels? As in, is it on the back panel under the window (behind upper metal panel, or behind lower carpet)? Or is it on the actual side panel with the jump seat (in front of jump seat, under carpet, or behind plastic b-pillar cover, etc.)? If you're not sure, that's fine -- you've been a ton of help already.

Thanks,
Mark

 

Its behind driver seat side behind the rear cab plastic panel

Found this diagram that shows RAP module location, #2, and other parts of anti-theft alarm system: https://ww2-secure.justanswer.com/up...0_210251_1.gif

Same place on extended cabs

And if lights are not flashing then alarm is NOT your issue, I just assumed you had already diagnosed alarm issue
Check fuse 24 in cab, starter motor activation fuse
And could just be failing starter motor

 

Ron,

Thanks for the diagram. I may have to wait till next monday to attack this (using alternate vehicle while I cuss at the truck . . .) , but will report back on RAP grounding effort.

Yes, definitely an alarm problem -- lights flashing, horn honking (when connected) and theft light blinking. All somehow related to the key cylinder damage (which would lead me to your tamper switch hypothesis, but the resistance checked out). Regardless, taking the entire RAP out of the equation (with subsequent loss of alarm system) should solve the problem.

More to come.
--Mark

 

Ron,

You're the man ! I followed your directions (ground the light green w/ purple stripe wire on the RAP module) reconnected the battery and the truck started without problem. Now here's the weird part -- just to check, I removed my temporary ground wire from the RAP harness and tried to start the truck and it started up fine. Very surprising. I tried it 3 more times -- no problem (see picture below with truck running and RAP module sitting on jump seat). So I don't know what's going on there, but it works fine. I appreciate all your advice. Thanks a bunch.

Summary of the problem and resolution for anyone reading this thread down the road:

1. Truck has pre-PATs anti-theft module (RAP).
2. Key cylinder was damaged during theft attempt causing the key to not be able to turn cylinder into the "on" position. Thus truck could not be started and damaged key cylinder could not be removed via the "normal" procedure of pushing the little retaining pin underneath and sliding the cylinder out.
3. I proceeded to drill out the little retaining pin underneath the column with a 3/16" drill bit. This was not easy to keep the drill centered because the retaining pin is rounded on the end, so the drill bit kept sliding to the side and chewing up the sides of the retaining pin hole. I ended up wallowing out the hole quite a bit and was concerned that the replacement cylinder would have too much slop in it. Eventually I chewed up enough of the retaining pin that I was able to put vice grips on the key cylinder and tap on the vice grips with a hammer and pop it out. [Ultimately I found that the wallowed-out hole had no detrimental effect, so don't worry about this).
4. I ordered a new Dorman key cylinder.
5. Note that the replacement cylinder will only slide in with the key turned to the on position so the retaining pin can retract. But in my situation, the little gear in the bottom/end of the key cylinder hole (that mates with the shaft on the end of the replacement cylinder) was still in the off position from when I yanked out the damaged cylinder. So I had to pull the gear out (you can use needle nose pliers or anything like that), and then put it back in the cylinder hole rotated a few notches to try to approximate the on position so the slot in the gear would mate up with the shaft on the replacement cylinder. To place the gear into the the cylinder hole, I stuck it on the end of a flat-blade screwdriver (using the slot in center of the gear) and put it in. Then I put the replacement cylinder in (with key in the on position) and tried the different key positions. This was a trial and error process. In the first couple of attempts the cylinder wouldn't rotate all the way to the start position (indicating the gear was not in the correct relationship to the cylinder). So take the cylinder back out, remove the gear, put the gear back in rotated by one gear tooth, and put the cylinder back in and try it. After three tries I hit the right combination. There aren't many possible combinations, so it won't take you many tries. Just be prepared for this.
6. Now, here was my big surprise -- after finishing the replacement cylinder installation, I reconnected the battery and the anti-theft system immediately activated. Horn honking, "THEFT" light blinking on dash, and no ability to start it.
7. I tried several things to no avail (read through this thread), but based on Ron's guidance I finally disconnected the RAP module. Note that the RAP module is inside the "B-pillar" immediately behind the driver, about 24 inches off the floor. You'll need to remove about 6 plastic trim panel retaining plugs to get enough slack in the trim panel (which is quite large) to get a socket wrench (11 mm) behind the panel and remove the two gold nuts that hold the RAP bracket. Then undo one plastic wire harness holder and lower the module out of the pillar (on my extended cab it came out through the jump seat opening -- not sure on regular cab). Disconnect the wire harness.
8. [NOTE: this step may be unnecessary -- try starting the truck by just disconnecting the RAP module, which worked for me]. Now I initially ran a temporary ground wire from the light green w/ purple stripe wire socket (look closely, there is a green wire with purple stripe in each connector -- but only one is clearly LIGHT GREEN).
9. Hopefully your truck will start by either just removing the RAP module, or by removing and then grounding the mentioned wire.
10. Good luck, hope this helps.

--Mark


Truck running after disconnecting the RAP module.

 

Good work

And very nice write up, it WILL help someone else down the road

 

Its gonna help me I'm trying it tonight!!