Inspection Using An Oscilloscope (Reference)

APP sensor (No. 2) signal 

Accelerator pedal released 

Accelerator pedal depressed 

PCM terminals 

• 1 AC (+)-body ground (-)

Oscilloscope setting 

• 5 V/DIV (Y), 5 ms/DIV (X), DC range

Vehicle condition 

• Idle after warm up
  Fig 2: Identifying Signal Waveform

  Courtesy of MAZDA MOTORS CORP.

Fan control module signal 

PCM terminals 

• 1AE (+)-body ground (-)

Oscilloscope setting 

• 5 V/DIV (Y), 5 ms/DIV (X), DC range

Vehicle condition 

• Idle after warm up
  Fig 3: Identifying Signal Waveform

  Courtesy of MAZDA MOTORS CORP.

Generator field coil control signal 

PCM terminals 

• 1AW (+)-body ground (-)

Oscilloscope setting 

• 0.5 V/DIV (Y), 2 ms/DIV (X), DC range

Vehicle condition 

• Idle after warm up
  Fig 4: Identifying Signal Waveform

  Courtesy of MAZDA MOTORS CORP.

Generator output voltage signal 

PCM terminals 

• 1AX (+)-body ground (-)

Oscilloscope setting 

• 2 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition 

• Idle after warm up
  Fig 5: Identifying Signal Waveform

  Courtesy of MAZDA MOTORS CORP.

A/F sensor heater control signal 

PCM terminals 

• 2C (+)-body ground (-)

Oscilloscope setting 

• 5 V/DIV (Y), 200 ms/DIV (X), DC range

Vehicle condition 

• Idle after warm up
  Fig 6: Identifying Signal Waveform

  Courtesy of MAZDA MOTORS CORP.

CMP sensor signal 

PCM terminals 

• 2S (+)-body ground (-)

Oscilloscope setting 

• 2 V/DIV (Y), 100 ms/DIV (X), DC range

Vehicle condition 

• Idle after warm up

CKP sensor signal 

PCM terminals 

• 2W (+)-body ground (-)

Oscilloscope setting 

• 2 V/DIV (Y), 5 ms/DIV (X), DC range

Vehicle condition 

• Idle after warm up
  Fig 8: Identifying Signal Waveform

  Courtesy of MAZDA MOTORS CORP.

Wastegate control solenoid valve signal 

PCM terminals 

• 2AA (+)-body ground (-)

Oscilloscope setting 

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

Vehicle condition 

• Switch the ignition to ON
  Fig 9: Identifying Signal Waveform

  Courtesy of MAZDA MOTORS CORP.

Purge control signal 

PCM terminals 

• 2AB (+)-body ground (-)

Oscilloscope setting 

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

Vehicle condition 

• Racing
  Fig 10: Identifying Signal Waveform

  Courtesy of MAZDA MOTORS CORP.

OCV signal 

PCM terminals 

• 2AF (+)-body ground (-)

Oscilloscope setting 

• 5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition 

• Racing

IGT1, IGT2, IGT3, IGT4 control signals 

PCM terminals 

• IGT1 (No. 1):2BA (+)-body ground (-)
• IGT2 (No. 2): 2AW (+)-body ground (-)
• IGT3 (No. 3): 2AX (+)-body ground (-)
• IGT4 (No. 4): 2AT (+)-body ground (-)

Oscilloscope setting 

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

Vehicle condition 

• Idle after warm up
  Fig 12: Identifying Signal Waveform

  Courtesy of MAZDA MOTORS CORP.

Fuel injection control (-) 

PCM terminals 

• Fuel injection No. 1: 2BB (+)-body ground (-)
• Fuel injection No. 2: 2BC (+)-body ground (-)
• Fuel injection No. 3: 2BD (+)-body ground (-)
• Fuel injection No. 4: 2AZ (+)-body ground (-)

Oscilloscope setting 

• 10 V/DIV (Y), 20 ms/DIV (X), DC range
  Fig 13: Identifying Signal Waveform

  Courtesy of MAZDA MOTORS CORP.

Vehicle condition 

• Idle after warm up

Fuel injection control (+) 

PCM terminals 

• Fuel injection No. 1, No. 4: 2BG (+)-body ground
• Fuel injection No. 2, No. 3: 2BH (+)-body ground

Oscilloscope setting 

• 20 V/DIV (Y), 400 us/DIV (X), DC range

Vehicle condition 

• Idle after warm up
  Fig 14: Identifying Signal Waveform

  Courtesy of MAZDA MOTORS CORP.