Replace your alternator
If alternator and battery test fine- then you may have a bad fusable link not allowing the alternator to charge the battery
Usually when your battery light will not turn off, you either are about to have generator problems, you have a bad controller, or you have a bad sensor. You need to have someone check it out.
If your 1997 Mercury Tracer has a battery light that blinks on and off while the car is running, it most likely means that the battery is not charging. This could be an issue with your alternator.
usually means that the alternator is not charging. So the battery is being drained.
This is a bad door sensor. My wife's Neon currently has this issue. Instead of dealing with it I just pulled the interior light out. The car complains about a fuse issue now that the light is not connected but at least the dome light wont drain the battery.
it is possible for a bad battery to make check engine light come on. if the battery wont hold a charge and the car is running mostly off the alternator current. the car usually will idle fine, but when you go to drive it the gauges will do strange things and the car wont run very well when you step on the gas. take it to advance and they will ck the battery for free, if the car will run long enough take the whole car, and they can scan it for stored codes and give you a general idea whats wrong with it
unplug your car battery
If the parking lights are on when the car is off its probably a switch issue.
The brake light switch is broken or out of adjustment.
could be a alt not charging or a loose wire on the alt or a bad ground
If it won't crank, which is probably what you really have going on, it means your battery went bad while you were driving.
Probably a bad ground from the battery to engine/body.