Evidently the alarm is responding to other RF signals, which is pretty bad. I would change the alarm 'brain box'. Clive > My son's '96 Aerostar has a wierd alarm problem. The alarm would go > off for no apparent reason(horn honks). Then he discovered that if he > was parked next to a GM product and the owner locked the GM doors by > FOB then the Aerostar alarm went off. If the GM doors were unlocked by > remote, them the Aerostar alarm cleared. When it alarms, the only way > HE can clear it, is by starting the Aerostar. > It doesn't do it all the time but a lot of the time. And sometimes it > will alarm when another Ford is unlocked. > > Anybody ever hear of this problem or any ideas? > > lbokc

"alarm brain box", is there a seperate box(besides the OBDII) for the alarm? Larry

As the son referred to in the original email (and joined the list today), I have more details and another question: Around the same time as the alarm started acting up, the drivers door would not unlock. The lock button works fine. The unlock button does not work. I replaced the buttons with no effect. I took it to a place just reporting that the drivers door would not unlock. They said it was the actuator in the door ($99 part plus $94 for one hour labor). But when they installed the new actuator, the drivers door still would not unlock (but would still lock). Service manager got up under the dash and then claimed that the alarm system was an add on and was affecting the door locks. His claim was that it was wired backwards - that the passenger door was supposed to only lock and unlock the passenger door and the drivers door was supposed to unlock all. LOL!! When I picked up the van (still not working), he didn't charge me anything since his solution (the actuator) was not the problem. Very nice!! When he claimed it was the after-market alarm, I mentioned the problem with the GM product setting my alarm off. He decided the two problems will be fixed by the same solution. Is the "alarm brain box" the solution to this problem? Wes

This all depends on wether or not the alarm system is still properly wired. If it isn't or if there is a bad connection themn changing the "Brain Box" will have no effect if the wiring is bad. I would check all connections first and then go on from there. The other option is the method that your mechanic is using to throw parts at it until you luck out and try the right thing. ~$200 for an actuator that that didn't fix it is just the beginning. Fortantly you didn't have to pay any money to learn that lesson but I would take the free lesson and start with a volt meter and a test light. If you can find the manufacture of the alarm system they will probably have a website with wiring diagrams that will walk you through the testing. I hope this info is helpful. Shane

Can the operating frequency for the alarm be changed to one that is less sensitive to other car alarms?   There should be a configurable set of dip switches on both the box and the hand held unit.   Jaime

There are no dip switches in the remote. The "programming" of the remotes is done via a series of locking and unlocking the doors followed by.... It's an interesting process that I have had to follow once when I replaced a remote. I will have to look to see if there is a way to change the frequency. Thanks for the suggestion. Wes

Then I would figure the alarm system is a generic one that has too close a operating frequency to other brands causing the problems you are experiencing.   I would disable it or change it for another system that is programmable.   Jaime
88 TC.
There are no dip switches in the remote. The "programming" of the
remotes is done via a series of locking and unlocking the doors
followed by.... It's an interesting process that I have had to follow
once when I replaced a remote.

I will have to look to see if there is a way to change the frequency.

Thanks for the suggestion.

Wes