Had the same problem myself, just keep troubleshooting down to the specific problem area, sounds like you have either a frequency/reciever issue or it might be your remote.. I actually had the samething happen to me twice, when Ifirst got my panzer 3, powered up the battery etc, turned on all the switches, would get flashing lights, but wouldn't be able to turn it on, everytime Iwould press the key, it wouldnt turn on..... soon realized after some tinkering that the key button needs to be held down for like 3 seconds (bad instructions) not pressed, got it working. Played with it for a week or two, then the samething happened again, exact same symptoms, transmitter on, tank swtich on, getting flashing lights, but it won't start up, started troubleshooting as you did, realized the frequency crystal on the remote (bottom right area of the remote) just needed to be pushed in a little tighter (guess it was a little loose), if that doesn't work, check also the crystal in the tank to make sure it's not loose either.