For the past 2 weeks my theft light indicator will come on when I start the explorer. The theft light stays on solid for 30 seconds and then starts blinking for 30 seconds and then goes off. This does not happen everytime I start the explorer but is getting more frequent. My mechanic is still researching the problem. He has eliminated the “key” being the cause. He has replaced parts in the ignition (switch, transceiver, covcer and contact). Thanks for any help on this issue. My explorer starts and runs fine— it is just this theft light problem .
Your chip loaded ignition key may be faulty. Dropping the remote and key on the ground can do this.
Have you tried another key?
Perhaps the security code needs reprogramming?
Thank you for replying.
I did try another key — no improvement.
Could there be a short in a fuse or electrical system to the dash board anti theft light?
If it is the security code…how do we reprogram it? or is that a dealer thing.
I thought if it was the code…the explorer would not start at all.
This has really got me and my mechanic stumped.
any thoughts are appreciated>
Reprogramming security codes is, unfortunately a dealer thing. However, that may not be the fault either. Anything can be happening when electronics are involved.
You said the vehicle starts and runs fine so I reckon the security code must still be valid.
You may be right about a short. Try tracing that anti-theft light wire back from the dash to it’s source, the wire could be rubbing the insulation off on metal.
Please let me know if you find the fault, ok?
I am guessing that the anti-theft system itself is failing. In other words, the systems knows it isn’t working so it’s blinking its light at you, but allows the car to start and run because that is a more fail-safe thing to do than shut the car down. This is probably going to take a dealer to diagnose.
Thanks much for your reply…I will let you know when I get it resolved.
I went to the Ford dealer today and the service manager put in a new PCM relay part because he had seen a similar issue with a Mercury car awhile back. Unfortunately…the relay didn’t help. In fact, the anti-theft light acted up while he was with me…he said that until it does it constantly…the computer won’t give a code on the problem. Sooooo…I guess I have to wait until the anti-theft light stays on constantly before I can get a diagnosis…go figure. Life is never dull 
thanks much
Try posting on a Ford board. You are more likely to find people with past experience like this or that understand the system. www.crownvic.net is a good site and these cars probably use the same PATS system.