Depends on how good the install looks but if you get under the hood and look for some extra cables on the battery follow them to the ecu of the alarm. Or pull some panals from the bottom og your dash on the right hand side and follow the wires from the fuse box and some of them will eventually lead to the alarm unit. Or looking under the hood again find the siren and it may have the brand right on it or one more time follow the trail. If you can get adn part numbers I would go to
www.directed.com and look it up there. They are the manufators of most of the brands of alarms (the good ones anyway). They make Viper, Python, Valet, Avital, Clifford, Rattler and about 5 more differnt brands.
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