Ok its a 95 ford ranger xlt. Ext. Cab 3.o 5 speed manual. Took it and had a compustar cs720 alarm. Installed professionally.well pay for pro install. Here is the problem i having locked my doors with alarm key fob and someone tried to get in the truck through drivers side.Alarm sounded but only horn and lights no siren. Now wont start even with the brain box removed. Help!!!!!!

 

Welcome to the forum

Horn is the siren I would think?

You probably need to plug the "brain box" back in, and then disarm the system with the fob
Any alarm that can be disabled by pulling the "brainbox" wouldn't be a good alarm system
So there will be a starter motor or computer disable relay inside the "brainbox" that must be used to start engine

See if you can find an installation wiring diagram for the system, and look for the "starter disable" wiring, thats usually all they have as that can be accessed in the cab wiring
They cut the starter motor activation wire at the ignition switch and run it thru the "brainbox" so starter won't work unless relay in "brainbox" is closed
If thats the case then you can jumper those two wires at the "brainbox" connector to restore starter motor function

Also call any local companies that used this brand of alarm, they may be able to talk you thru disabling the system manually, or email you a diagram or instruction for by-passing it

Each alarm system uses its own methods to prevent theft, so there is no one answer for all systems

 

The key fob would not disarm it. At the time of install the horn did not work so it has a siren. So had ford look at it it does have a factory keyless entry which has a starter kill relay they relay was way up in the dash had. To replace it then it was fine 400.00 later .

 

Glad you got it back on the road