2006 honda crv battery goes dead overnight

search , " parasitic drain "

a Parasitic drain is a short in a circuit. To locate the short ....1st charge the battery......2nd disconnect the negative cable from the negative battery post... 3rd remove the fuses that provide power to the dome light and radio as these draw power normally when the door is open and to maintain station settings and clock. Use a 12-volt test light inline between the negative battery post and negative cable removed. basically, connect one end of the test light to the negative battery post and touch the other end to the negative battery cable removed so it is now inline. the light should not be lit on the 12-volt test light. If it is remove one fuse at a time to see if the test light goes out. if it doesn't replace the fuse and move to another until you find the one that turns off the test light. That would be the circuit that is the problem. Let's say it's the brake light fuse that makes the test light go out. I would check the brake light bulbs and sockets first for a bad bulb or corroded socket or bad ground. Then maybe the brake light switch actuator and so on.