Car won't start, has no power
 

well i drove home after work, parked my car underground, then no more then two hours later went to start it again. turned the key over to crank and EVERYTHING died and shut off, not a single light, chime or anything was working. connected a booster pack and still nothing. left the battery disconnected for a dew hours then got it checked and it was fully charged and 100% health.
had this problem once before but lights were dim and not off.
first time it happened i could bump-start it. this time didn't work, plus not that much room in underground parking..

update: i looked over the wires and they seems to be okay for the most part. i hooked-up the fully charged battery and got lights again, stereo and system worked fine, but once i tried to crank, it clicks once, then dies. turn the key all the way back and the chimes will kick in when the door is open. once i turn to accessory, nothing, turn the stereo on again, shuts off right away..

anyone with suggestions or similar experiences?

Car is a 2000 civic coupe DX

maybe the main relay went, it's a common problem on EG, not sure about EK's though.

Probably a connection problem.

its not a main relay issue. I would check for good solid connections and/or corroded wires

alternator not charging?

Check & clean your ground connections at the battery, body and transmission.

did you tighten the battery clamps when you put them on or did you just put them on there?