JVC GR-D90U: Camcorder works when plugged in but not when on battery power only.

With my JVC GR-D90U camcorder, it works when it is plugged into a wall socket but doesn't work when on battery power only. The battery charging light even flashes when the camera is plugged in. I bought a new battery and checked the leads but it still won't work on battery power. Does anybody understand the circuitry of this camera well enough to give me an idea of what might be wrong? Thanks for any advice.

Reply