MEFI Fuel Injection
Shift Interrupt Input
Shift interrupt connector
The shift interrupt input is only used in high horsepower DPX applications (DPX 375, 420, 500 and 600). The white with a blue tracer wire from ECM connector J1 pin 20 has 11-11.5 volts on the wire supplied from the ECM. The ECM watches for this voltage to be pulled to ground. If the vessel is equipped with a shift interrupter switch, it is located in the shifter assembly. As the shifter is moved from neutral towards clutch ahead or astern, the switch closes and grounds the circuit. By the time the shifter has reached the clutch position the switch is again open. When the ECM sees this input it then looks at throttle position and engine RPM. If the engine is at idle, the ECM kills half of the injectors in order to reduce torque output of the engine during the shift. To summarize: any time the circuit is pulled to ground AND the engine is at idle (closed throttle), the ECM will kill half the injectors. This connector looks identical to the trim sender connector and sometimes gets plugged into the trim sender. This will cause a loss of half of the injectors at closed throttle when the drive is trimmed down.
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