2009 Yamaha F40 Outboard Service Manual, Page 115Get this manual
Fuel control units and components 3Connect the tester probes to the highpressure fuel pump coupler terminals, and then measure the input voltage within seconds after turning the engine start switch to "ON
7Check the wiring harness for continuity1 250 51 52
High-pressure fuel pump input voltage: Blue (L)Black (B) 12.0 (battery voltage) 4Turn the engine start switch to "OFF 5Measure the resistance of the high-pressure fuel pump motor