Sounds like a wiring problem...dead short to the fuel pump - the fuel pump is getting direct battery voltage.....time to start tracing the wiring through the ski.
Sounds like a wiring problem...dead short to the fuel pump - the fuel pump is getting direct battery voltage.....time to start tracing the wiring through the ski.
What about it? The short could be anywhere, of course.....you could have a corrosion bridge somewhere/anywhere....I'd start by first checking all the harness connections, pulling and re-seating them, cleaning all electric contacts, etc....pull and re-seat the fuel connection first.
You said the DESS key was not installed, so the mpem gets battery voltage but with no key installed, the ski is still technically sleeping....hitting the S/S button with no DESS will wake the ski up, hitting the S/S button with DESS installed should fire up the ski.
Could be.....your fuel pump pins are located in Connector #4 pins 24 (negative - ground) & #26 (positive voltage).
So, if you connect the battery (and the pump comes on like you said), then disconnect MPEM connector #4 to see if it stops. It should....that'll tell you that the fuel pump is getting direct battery volatge
Once the DESS key is installed, the fuel pump should run for 2 seconds to pressurize the fuel rail. If the pump does not shut off, the ECU/MPEM could be bad.
The fuel pump pins (#24 & #26 are in the MPEM connector #4).