Oops, I didn't realize it was an aftermarket alarm; sorry. Sure would be nice if that's all it is. Be sure your mechanic measures the battery voltage while the engine is running. Rasmataz brought up the overcharging issue. 14.75 volts is about the highest you want to see. It's still rare for overcharging to explode a battery but I suppose it's possible. If you do a lot of short trip driving, your new battery might survive some overcharging for a while but with a lot of highway driving the sides of the battery will start to bulge out and the water in the acid will boil out. That will also lead to the formation of the greenish-white hairy corrosion around the posts when the acid condenses there. I'll feel better knowing exactly what the charging voltage is.
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Wednesday, March 9th, 2011 AT 10:20 PM