Tuscan ecu voltage

[stlol]

Does anyone know what voltage the ecu should be getting, should it be a stable regulated 12v or does it get upto 14v that the alternator puts out?

[paul1962]

There is no distributed regulated 12V supply AFAIK, so the ecu will see anything from 14V when the engine is running down to considerably less (<9V ?) during engine start.

[aide]

The internal ecu logic runs at 5v.
( please correct me if I'm wrong )

[Sardonicus]

It will see battery voltage and will make corrections to injection duration etc as necessary with battery voltage fluctuations

[stlol]

Ok thanks all,
I was originally seeing only 9.5 v at the fuel pump, then whilst trying to trace why I noticed the full voltage at the ecu.
Fuel pump voltage was fixed by swapping the relay, I also see that there is a 5v feed to a couple of items, how is this generated and from where as it is present with the ecu disconnected.