Sounds like a factory system to me. Chick probably bought a new fob.
I've never seen an aftermarket installer hook into the dash wiring, for one.
They usually just drill a hole in the middle of your dash, and put a crappy looking led thru it.
Search the site for threads about this problem; it's not that rare. There is discussion of wire colors, and where everything is, iirc.
Short version, the alarm has five sensors, and if one of them intermittently grounds, or the car wiring shorts, it will go off after a bit.
Not easy to find, as they are all connected in parallel, so...
I'd look at the door switches; they're in the locks, and probably need new lube and tlc. The door lock actuator works a part in the same assembly...
Driver's door gets the most use...
Red '96 Cougar XR-7 240k mi. '02 4R70W, PST DS : '03 PI engine, 04 maf, 24lb injectors, 2.5" exhaust, '02 4r70w + Jmod, DirtyD0g TC + cooler + 3/8" lines, 255 walbro fp. Alpine system.
Black '96 Cougar XR-7 (Lazarus) 210k mi PI Intake, '02 4R70W, Jmod, PST DS, GrogTune, Konis, Mark LCA+Poly, racecougar Custom Engine Chain, and JL and racecougar Bracing.
Black '97 Tbird Limited Edition, '02 4R70W, 255 walbro, PST DS, PBR Brakes&SS lines, Toicko Blues & Springs, GrogTune.
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