Fuel injection control (-) signal

Fig 1: Fuel Injection Control (-) Signal Waveform

Courtesy of MAZDA MOTORS CORP.

PCM terminals 

• Fuel Injection No. 1: 1DO(+)-body ground(-)
• Fuel Injection No. 2: 1DW(+)-body ground(-)
• Fuel Injection No. 3: 1EA(+)-body ground(-)
• Fuel Injection No. 4: 1DS(+)-body ground(-)

Oscilloscope setting 

• 20 V/DIV (Y), 50 ms/DIV (X), DC range

Vehicle condition 

• Idle after warm up