1996-2005 Suzuki DF40, DF50 Four Stroke Outboard Service Manual, Page 92Get this manual
3-37 ENGINE CONTROL SYSTEM (3) Connect the tester probe(Red) to each terminal(Voltage)
Injector No.1 No.2 No.3
Terminal A4 A7 A8
Wire color Engine OB BY RW Test cord BR BY Lg
A Peak voltage reading (NEG) 0V level for peak voltmeter 12V
(4) Crank engine and measure voltageFuel injector operating signal10 FUEL PUMP SECOPERATING SOUND Turn ignition switch ON and check for fuel pump operating soundFuel pump operating soundSounds for approx3 seconds only