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i have a 2004 civic ex. yesterday the green key light kept blinking the whole time i was driving it and it started funny. i looked up what it meant and it said something about the coding. so i used another key i had and it started fine and no green key light, until this morning, it wouldn't start at all. i have 3 keys and none of them worked. when i tried to start it, it would sound like it struggled to turn over, only doing so 3 times, i dont think it did turn over but it made the attempt. then all the lights would blink with a clicking noise at the same time. i have read that it may be the battery? or the immobilizer? any advice would help. and if it might be the immobilizer how is that fixed? put a new ignition switch in? or re-programming? and by any chance a rough cost. i called a dealership they said it might be the ignition switch, but 90$ just for a diagnostic jeez. thank you.