MS V 3.0 fuel pump circuit Expertise needed.
Posted: Tue Jan 24, 2006 2:56 pm
This subject has been discussed at length in other threads and I've searched high and low but would appreciate some clarification.Correct me if I'm wrong but the "fuel pump mod" that Peter Florance has devised is required because the Megasquirt connection #37 provides a ground for the fuel pump and what is actually required is +12v to supply the coil of the L-Jet fuel pump relay is that correct ?
The circuit he has devised changes connector #37 to a +12 V output on the DB37- correct ?
The reason I'm asking is that I am building a V3 MS II board and the fuel pump drive circuit is different from the board which Peter Florance modified. (Anybody know why it was changed ?)
Has anybody simply used an external relay to address this issue ? It would be very simple to use the MS ground on pin # 37 to pull in a relay coil powered from 12V external and supply + 12 through the relay contact to the fuel pump relay wouldn't it ?
The circuit he has devised changes connector #37 to a +12 V output on the DB37- correct ?
The reason I'm asking is that I am building a V3 MS II board and the fuel pump drive circuit is different from the board which Peter Florance modified. (Anybody know why it was changed ?)
Has anybody simply used an external relay to address this issue ? It would be very simple to use the MS ground on pin # 37 to pull in a relay coil powered from 12V external and supply + 12 through the relay contact to the fuel pump relay wouldn't it ?