Tom,
Welcome to the TDR and perhaps take a moment to fill in your signature for reference.
This subject matter has been discussed many times and you can research this in "Search Forum" from your user panel.
None the less, I too have experienced this same occurence. It appears the security systems of our vehicles are sensitive to RF (radio frequency) fields. You might take notice of where this syndrome occurs. Look for large transmitting towers with various antennas. Perhaps microwave parabolic dishes or even standard commercial broadcast antenna installations where you would be subjected to thousands of microvolts, of RF, being imposed upon your CTD. Close proximity to such installations or even being in a direct RF radiation path can cause the security system to false. None of us have gone out with RF Spectrum Analyzers to compute the "mix" of various RF signals to determine what "mix of frequencies or fundamental frequency" is actually causing this to happen. It would be very time consuming and then we need to research what input component (or system device) is sympathetic to such RF overload that causes it to react in an improper manor. Unfortunately our beloved CTD's are not "bullet proof" when it comes to strong electromagnetic and electrostatic fields of radiation. Military vehicles and aircraft undergo such engineering research prior to being employed in the field. In extreme cases not all possibilities can be accounted for and a "glitch" in a sensitive electronic device or system can lead to disaster.
I'm sorry I have no answer to actually "fix" the situation but, perhaps this incite will provide an understanding.
Cheers
William
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