Guys, remember that this is a 280zx. It's the warning display.
Kev, the manual isn't much help.
If none of the specific error symbols are displayed, Stop (lights), Head (lights), Tail (lights), Wash (windscreen washer level) or Water (radiator level), a red light is "Indication that there is a malfunction". It gives no information beyond that.
I guess this means none of those five items are faulty but that leaves a lot of other stuff to check. If your car runs rough, start there.
The manual can be downloaded from the HybridZ site.
Sorry I can't be more help, my 280zx also has the red light on at the moment, but it runs fine.
Pete.