Fuel injection control (-) signal

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