MSefi.com read only forum (Jan.15,2018)

When I built the MSII about a year ago, there was an ocasional issue with the fuel pump light on the stim not illuminating. Now in the car, there is occasional issue with the fuel pump not running - at least it is consistent.

Best I can tell, the MS controller switches the fuel pump relay by taking the ground wire of the controll side of relay low.

Can anyone guide me to which components are part of the fuel pump control circuit? I will carefully check those solder connections and components. I suspect it is something there.

Otherwise the controller works.

Thanks
Mark

Hey all,

I found the circuit schematic after I posted. Sorry for the bother.

Also reviewed it with a couple of engeineer friends who understand such things. Learned a lot about the current and voltage protection that the transistors and zener diode provide. Now viewing transistors vs. FETs in a whole new light.

I also know where to look for solder and component issues.

Thanks
Mark