Originally Posted by Day VG
This might explain why my car wouldn't start when a PFC ECU was fitted then. The car cut power to the ignition circuit so that nothing at all happened when you turned the key. Even when the original ECU was replaced it made no difference. A ;'work around' was found in the end, but lots of head scratching in between.
Transponders are usually powered by the radio signal that interrogates them, so I doubt if there is a battery.
what was the workaround??