bypass works on and off

Does it have old keys or newer jewel keys?

I have not had an issue with any of those. They always worked.

for those that don't know, this is from directechs:

"guys have tried insulating the 556u box without much success. What we are suggesting is to put the key in the freezer for 30 minutes, then immediately put it back in the U box. At that point re-position the ring so it will read with the key frozen. Freezing the key forces you to place the transponder ring EXACTLY where it needs to be during RS. When it is frozen it sends out a very weak signal that will only be picked up if the ring is placed perfectly on the key cylinder."

and

"The 556u broadcasts a known key frequency to the vehicle. Ford keys have a terrible broadcast ability when cold, thus 99% of all "won't start cold" issues. By freezing the key you are duplicating what happens to the key overnight while sitting in the vehicle"

PKF3 programs in like a key and goes through the data wires. So if it works it works.

Check tach programming. Have customer go out in late night or early morning and sit in it. Watch theft light. If it starts flashing when remote starting then you have an issue with security. If it doesnt, which I am thinking, you got a tach issue.

Just installed r/s and bypass 2 weeks ago.....problem...sometimes it starts, sometimes it doesn't....thought it was a bad bypass..cranked but theft light would flash....but after checking, found the "ground when running line" from r/s to bypass was dropping out before car started. Ran line from bypass to direct ground...now works everytime!!! In your expert opinion, will this hurt anything?? Thanks for reply.