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Theft Light - Please Help!

  • Thread starter Thread starter Mprado1
  • Start date Start date Mar 20, 2021
  • Tags Tags
    cobra ignition no spark spark theft theft light
M

Mprado1

New Member
Mar 20, 2021
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Florida
Mar 20, 2021
#1
  • Mar 20, 2021
  • #1
Hello everyone,

This is my first post as I'm just joining and I searched but didn't find the specific problem I'm having.

I recently brought my late brother in law's 1995 Cobra home. It has sat for 13= years and hasn't been touched. It had a bad fuel pump and the tank was trashed so I replaced the tank and pump with one from a donor '95 GT. The car has a Vortech V2 on it with the ignition and FPR to match. It looks to be an older MSD distributor and Motorcraft plugs and wires.

I'm getting fuel pressure at the rail but no spark. My dilemma is that the theft light flashes constantly after a few seconds of opening the door. I've unplugged the harness in the trunk at the anti-theft module and the light stops flashing but still no spark. After plugging the harness back in the light returned and after a few minutes, the horn went off and stayed on continuously (not beeping like a triggered alarm) until I pulled the battery terminal.

I've only begun to diagnose it but so far, it leads to the anti-theft system. I plan to replace all the basic tune up parts - plugs, wires, cap & rotor but I'd like to at least confirm that it's not an anti-theft issue.

Thanks in advance for any input!
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
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polk county florida
Mar 21, 2021
#2
  • Mar 21, 2021
  • #2
When you open the door and the alarm goes off, does it stop when you turn the ignition to the on position?
 
M

Mprado1

New Member
Mar 20, 2021
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Mar 21, 2021
#3
  • Mar 21, 2021
  • #3
General karthief said:
When you open the door and the alarm goes off, does it stop when you turn the ignition to the on position?
Click to expand...
Opening the door isn't the only thing to trigger the horn, it will randomly just start and its one continuous honk its not intermittent like an alarm would normally be. I've also not found any way to turn it off, no sequence of lock/unlock/key on or off has done anything.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,827
10,508
203
polk county florida
Mar 21, 2021
#4
  • Mar 21, 2021
  • #4
When the horn goes off is the lights flashing?
 
M

Mprado1

New Member
Mar 20, 2021
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Florida
Mar 22, 2021
#5
  • Mar 22, 2021
  • #5
General karthief said:
When the horn goes off is the lights flashing?
Click to expand...
No, the lights are not flashing as an alarm would - only the horn is activated.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,827
10,508
203
polk county florida
Mar 22, 2021
#6
  • Mar 22, 2021
  • #6
It may be unrelated to the theft system
Horn relay, or stuff under the steering wheel, the name escapes me right now, find the relay and pull it or un plug the horns
Does the theft light go out when you turn the key on?
 
M

Mprado1

New Member
Mar 20, 2021
6
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1
Florida
Mar 23, 2021
#7
  • Mar 23, 2021
  • #7
General karthief said:
It may be unrelated to the theft system
Horn relay, or stuff under the steering wheel, the name escapes me right now, find the relay and pull it or un plug the horns
Does the theft light go out when you turn the key on?
Click to expand...
The theft light stays flashing with key on.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,827
10,508
203
polk county florida
Mar 23, 2021
#8
  • Mar 23, 2021
  • #8
The key may not be doing whatever it is supposed to do so the module can read it, call a mobile locksmith to see how much they would charge to program a new key,
Do you know if the cluster or anything has been swapped?
 
M

Mprado1

New Member
Mar 20, 2021
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1
Florida
Mar 23, 2021
#9
  • Mar 23, 2021
  • #9
General karthief said:
The key may not be doing whatever it is supposed to do so the module can read it, call a mobile locksmith to see how much they would charge to program a new key,
Do you know if the cluster or anything has been swapped?
Click to expand...
Its the original cluster and the key isn't a chipped key. With the anti theft module unplugged, the light goes off and everything else in the car functions as it should but still no spark. I'll be replacing the distributor today to try to get the PIP signal issue resolved and if the car starts with a new distributor then I'll address the horn issue afterwards.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,827
10,508
203
polk county florida
Mar 23, 2021
#10
  • Mar 23, 2021
  • #10
It is my understanding that if the theft light is flashing it is not reading the key (yes the key should be a chipped key if it has factory anti theft) and car will not start, I could be wrong, but whatever.
 
M

Mprado1

New Member
Mar 20, 2021
6
0
1
Florida
Mar 23, 2021
#11
  • Mar 23, 2021
  • #11
General karthief said:
It is my understanding that if the theft light is flashing it is not reading the key (yes the key should be a chipped key if it has factory anti theft) and car will not start, I could be wrong, but whatever.
Click to expand...
The only key that exists for this car is the original factory key and fob. This key is just a square Ford key with plastic cover and is a non chipped key. Unfortunately, I don't know anything about these cars and their factory anti theft options and several people have told me that if it were an actual anti theft problem, the starter would be disabled (which is not the case here). The chipped key (PATS) wasn't introduced until 1996+ vehicles so I can only go by that. As far as the module goes, I've seen the same exact year and trim level of car without the factory anti theft module (harness is there with pigtails but no module) and they operate just the same.
 

General karthief

wonder how much it would cost to ship you a pair
Mod Dude
Aug 25, 2016
27,827
10,508
203
polk county florida
Mar 23, 2021
#12
  • Mar 23, 2021
  • #12
Ok
 

SorsCode

20+ Year Stangneter
Jun 10, 2003
1,020
428
113
St. Louis, MO
Apr 3, 2021
#13
  • Apr 3, 2021
  • #13
Plug the Anti-Theft back in. It will prevent you from starting. The light should flash with the door open. Lock the car and it should flash a few times and stop, unlock with the key fob. After that check for spark, if no spark time to start check things like ignition module and distributor. I have the anti-theft module in all my cars.
 
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