Originally Posted by
Old guy
If you have an immobilizer installed and you didn't even get a click from the starter when you had the jumper cables connected to the other car, I would be suspect that something is up with the immobilizer and it is preventing the starter motor circuit from operating. When you use jumper cables to connect the NSX to another car, try briefly turning the headlights (or the emergency flashers) on the NSX on. They should work fine off of the other car's electrical system. If the headlights won't come on then there is something wrong with the NSX electrical system or you are not doing the jump process correctly. Even with a dead battery, when the NSX is connected to another vehicle you should be able to engage the starter and the motor should run. Once the engine is running, it is theoretically possible to disconnect from the other car and run on just the alternator; but, don't push your luck with that.
If the charger is giving you a warning light I would treat the battery as 'time to recycle'.