Is ECU red light suppose to be on or off while turned over?

[timmyk]

Maybe someone can check for me, I'm trying to diagnose my car, it runs great and all but I had a rough start the other night and I'm checking over everything to prevent future issues.

So when the car is turned over is the ecu light suppose to be on [red] or off?

Because currently mine is off when turned over but it runs great. I'm kind of stumped on this and maybe some of you guys can chime in?

Thanks.

[wangan_cruiser]

It supposed to be lit up when your car is running.

[S13FASTBACKSR]

woah hold up wangan...on? no it supposed to be off when the engine is running. On means bad ecu.