Sorry KenshiBike, but it sounds like you are out of luck. Definitely sounds like the battery has failed. NiteRider makes their lights so that when they fail you have to buy another one. They have made this one so that the battery is not user replaceable. On their lights that use external packs, they use an extra wire so that when the battery dies on those models you can't just go out and buy a replacement battery from someone else, you are forced to buy a replacement battery from them. They price their replacement batteries so that they are almost as expensive as buying a brand new light. I would go ahead and give them a call but I would not expect them to much about it.
davidad - Those batteries you linked to will never work with the NiteRider Lumina 650. It has an internal battery. Also as I mentioned earlier, you can not just buy a Li-Ion pack of the interweb and use it on a NiteRider light that uses an external battery pack. They treat their lights as being "disposable" and want to force you to buy another light so they price their replacement batteries so that they cost almost as much as a new light would be.
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Last edited by unterhausen; 01-24-14 at 07:58 AM.