why is my sercurity light blinking and drain my battery
If you find that when you are trying to start and the security goes off, your battery was either disconnected or low enough to shut off the computer. Can fix that by taking your key and locking and unlocking the driver's side door. If so, it's either your battery is not keeping charge, or perhaps an alternator. Try taking it by Advanced Auto parts (if you can) and have them quick test it. Your question is kinda vague, did my best.
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