2004 Ford Taurus. Installed after market Prestige starter. model: APS-620N. Door lock and unlock work. Trunk works. Parking light do NOT light up when programming or locking/unlocking doors. Not receiving tach signal. Unable to start car with remote fob. When I try to start car with fob, I hear ticking presumably from the parking light flasher relay. Counts 7 times which according to diags. Says tach not learned. Have rechecked tach connections several times. Thanks.

if the key turns in the cylinder then the door panel needs to come of and check the lock rods if key does not turn cylinder then the cylinder was changed at one time and there is another key for the door. see if the key works in other locks on car

I assume you have the correct key. (sorry, I have to ask) For all doors locks and the trunk lock to not work, at the same time, is very unusual.

Try squirting some light oil in the locks, like WD-40, then push the key in and out a few times.
Wait a couple of minutes, and then try to unlock the doors and trunk.

If you still cant get in the car, and your 100% positive you have the right key, call a lock out service.

They can get it open, and your insurance may cover it. Hope this helps.

yes i have lol after alot of asking and tryin, it was the head light switch

Sounds like the keyless entry system is on the fritz. You will probably have to get a new brain for the keyless entry system.

sounds like you may have the wrong key

In the trunk on the trunk mount support there should a sticker with the original keyless code number, reinstall this number into your system and try it. The original number will reset the system.

it sounds like it is in the door lock actuator and the security mode itself now if you have a remote starter installed you may have to take it back to the person who installed it because the problem maybe in your security system

" turn the key on engine off 8 times. the doors will lock and unlock. push one of the buttons on the key fob and the doors will lock and unlock. do this for each remote that you have. when you are done turn the key off. the door locks will lock and unlock. the remote fob should work after this."
From My SecuriLock..

Try the trunk switch next to the driver's seat.