Flashing anti-theft Light


Art138

GT Owner
Mark II Lifetime
Jan 4, 2011
629
Weston,FL
Recently,upon start up the anti-theft red dash light blinks,starter cranks, but car will not start. I have to cycle the ignition key off/on a few times before I get the steady red light. I know this was discussed in a thread but cannot find. I remember that the ground connection from the battery should be checked (done). Battery is new/charged....Checked relays to ensure they were not loose. Checked for codes using the STC - none indicated. Symptom first appeared when the car stalled at a stop light. Anyone with this experience or know where I can find the thread?
 

Xcentric

GT Owner
Mark II Lifetime
Jul 9, 2012
5,213
Myakka City, Florida
Can't help, but I'll give the thread a bump. Stop light stalling is often MAF sensor related, especially on a windy day, but if it's MAF the car will restart normally.
 

Kingman

GT Owner
Mark II Lifetime
Aug 11, 2006
4,072
Surf City, USA
You have fallen victim to the 'ol "Clarkston Dilemma". First I must ask........do you have a short randy friend with a penchant for old American muscle cars and another friend that's an aged hippy?
 

Kingman

GT Owner
Mark II Lifetime
Aug 11, 2006
4,072
Surf City, USA
Proposed answer -> go back to the battery ground at the chassis. Disconnect and sandpaper away the paint until you see bare metal on the chassis. Re-connect battery ground. You should be fine now.

BTW - if you are unsure about the "Clarkston Dilemma"..................you may be subject to having your FGT ownership privileges revoked.

Enjoy your holidays!
 

Art138

GT Owner
Mark II Lifetime
Jan 4, 2011
629
Weston,FL
Proposed answer -> go back to the battery ground at the chassis. Disconnect and sandpaper away the paint until you see bare metal on the chassis. Re-connect battery ground. You should be fine now.

BTW - if you are unsure about the "Clarkston Dilemma"..................you may be subject to having your FGT ownership privileges revoked.

Enjoy your holidays!

Yes I found that thread about the "Clarkston dilemma".....apparently caused by the UK mandated vehicle demobilizer for those imports. Either taking out the relay from the power distribution box & cleaning the ends; or the negative ground re-connect seems to have solved the issue. Thanks for the suggestions...
 

roketman

GT Owner
Mark IV Lifetime
Oct 24, 2005
8,005
ma.
Good news!
Glad you got it sorted out
Another reason for thanks on thanksgiving! Our forum members!
 

bonehead

GT Owner
Mark II Lifetime
Aug 18, 2012
2,814
Houston, TX
All ready to head out to the local C&C this morning and the the car wouldn't start. Gauges work, car won't turn over, not even a click from the starter. Theft light is blinking away. Cleaned the ground wire with some APC. Checked to see of the fuses were seated in the power distribution box. Nothing. Heading out to Home Depot to get some sandpaper.

Briefly inspected under the clamshell. Nothing obviously loose or melted. Anything else I should be checking if sanding the ground doesn't work?
 
Last edited:

RALPHIE

GT Owner
Mar 1, 2007
7,278
Anything else I should be checking if sanding the ground doesn't work?

(push in the clutch) :lol
 

bonehead

GT Owner
Mark II Lifetime
Aug 18, 2012
2,814
Houston, TX
(push in the clutch) :lol

After sitting there perplexed for a minute, I was wondering if I wasn't doing something obvious. So I DID try pushing the clutch in harder thinking I wasn't engaging the button. Nope:(
Off to Home Depot....
 

paul b

GT Owner
Nov 2, 2006
810
Do you have a custom or canned tune, try putting back the stock tune.
 

bonehead

GT Owner
Mark II Lifetime
Aug 18, 2012
2,814
Houston, TX
Do you have a custom or canned tune, try putting back the stock tune.

I could try this easy enough. Do you have personal experience with this issue and a custom tune?
 

bonehead

GT Owner
Mark II Lifetime
Aug 18, 2012
2,814
Houston, TX
Well, chalk this one up to the WTF files.
Sanded down the negative lead and chassis ground, reconnected......nothing. Still had the flashing theft light.

Corresponded with Even Guyett (thank the lord for him) who eventually suggested that I try another key. Well, I had and have been using Andrew's latest key. I had some issues with it in the past which were resolved with a new circuit board. I put in one of my original keys.....theft light gone. Ok. Tried the second original key. Theft light still gone. Ok, the aftermarket one is sure NOT to work as it has to be the culprit. Andrew's key now worked. Seriously, WTF? Only thing I could think of was one of the original keys reset something (the theft deterrent system which was stuck in 'on' position for some reason) and now allowed all the keys to work.

Leaves me very uneasy though. I don't know if it was Andrew's key that was the original culprit? Full disclosure, I admittedly cycled the lock/unlock button several times before I tried to start the car this morning to check my passenger side signal lamp which had gone on the fritz earlier this month. Perhaps that 'locked' the theft deterrent system to the 'on' position?

Well, unless someone can confirm this theory, I need to either get rid of the aftermarket key (which I don't want to since I like it otherwise and paid good money for it) or always bring an original with me (which is just absurd).

Cliffs Notes: If your engine doesn't start and the theft deterrent light is flashing, try one of your other keys.
 

Xcentric

GT Owner
Mark II Lifetime
Jul 9, 2012
5,213
Myakka City, Florida
Explains why your car is so slow. You were racing in limp mode.
 

BlackICE

GT Owner
Nov 2, 2005
1,416
SF Bay Area in California
Explains why your car is so slow. You were racing in limp mode.

Whipples are like Viagra for a FGT!
 

bonehead

GT Owner
Mark II Lifetime
Aug 18, 2012
2,814
Houston, TX
Forgot to update this. After corresponding with Andrew, he instructed me to open the key and see if the theft transponder was either broken or loose. This is an oblong glass piece that is glued inside the key housing. I opened up my key to find it loose and floating around inside. If this part is not situated at the edge of the housing adjacent to the ignition, it will not deactivate the theft system rendering the car immobile. I reglued the transponder and voilà, functional key. Don't recall dropping it, but if you jar or drop your aftermarket key and find that your car no longer starts, this is another possible reason.