Hi, I have an early (75) v12. According to a wiring diagram I have the fuel pump relay is 'hot' as in constant 12volts supplied, regardless of ignition switch position. Would this be correct?
Thanks.

 

Sort of.

Depends as to whether its a "Fuel Infected" engine or a "Carby model".

For the Infected:

The Brown heavy wire is 12v HOT, then the ignition switches the relay ON, and then the other 2 wires are the PUMP, and EARTH. Earth is via the ECU, and its timer feature.

For the Carby:

Same deal, except the Earth is via a reverse oil switch, I THINK, as it has been a very long time.

 

Fuel infected. That makes sense. Ta very much.