Throttle control (+) signal

PCM terminals

2A (+)-Negative battery terminal (-)

Oscilloscope setting

5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Idle (Accelerator pedal released)

Throttle control (-) signal

Fig 1: Screen Display - Throttle Control (+) Signal Waveform

Courtesy of MAZDA MOTORS CORP.

PCM terminals

2B (+)-Negative battery terminal (-)

Oscilloscope setting

5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Idle (Accelerator pedal released)

Fig 2: Screen Display - Throttle Control (-) Signal Waveform
Courtesy of MAZDA MOTORS CORP.

Purge control signal

PCM terminals

2C (+)-Negative battery terminal (-)

Oscilloscope setting

2 V/DIV (Y), 0.1 s/DIV (X), DC range

Vehicle condition

Idle after warm-up

Fig 3: Screen Display - Purge Control Signal Waveform
Courtesy of MAZDA MOTORS CORP.

OCV control signal

PCM terminals

2E (+)-Negative battery terminal (-)

Oscilloscope setting

2.5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Idle after warm-up

Fig 4: Screen Display - OCV Signal Waveform
Courtesy of MAZDA MOTORS CORP.

CMP signal

PCM terminals

2S (+)-Negative battery terminal (-}

Oscilloscope setting

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

Vehicle condition

Idle after warm-up

CKP signal

Fig 5: Screen Display - CMP Signal Waveform

Courtesy of MAZDA MOTORS CORP.

PCM terminals

2W (+)-Negative battery terminal (-)

Oscilloscope setting

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

Vehicle condition

Idle after warm-up

Fig 6: Screen Display - CKP Signal Waveform
Courtesy of MAZDA MOTORS CORP.

Generator field coil control signal

PCM terminals

2AI (+)-Negative battery terminal (-)

Oscilloscope setting

0.5 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Idle after warm-up

Fig 7: Screen Display - Generator Field Coil Control Signal Waveform
Courtesy of MAZDA MOTORS CORP.

Generator output voltage signal

PCM terminals

2AJ (+)-Negative battery terminal (-)

Oscilloscope setting

2 V/DIV (Y), 1 ms/DIV (X), DC range

Vehicle condition

Idle after warm-up

Fig 8: Screen Display - Generator Output Voltage Signal Waveform
Courtesy of MAZDA MOTORS CORP.

Ignition timing signals

PCM terminals

IGT1 (No. 1):2BA(+)-Negative battery terminal (-)
IGT2 (No. 2): 2AW (+)-Negative battery terminal (-)
IGT3 (No. 3): 2AX (+)-Negative battery terminal (-)
IGT4 (No. 4): 2AT (+)-Negative battery terminal (-)

Oscilloscope setting

Fig 9: Screen Display - Ignition Timing Signal Waveform

Courtesy of MAZDA MOTORS CORP.

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

Vehicle condition

Idle after warm-up

Fuel injection signals

PCM terminals

Fuel Injection No. 1: 2BB (+)-Negative battery terminal (-)
Fuel Injection No. 2: 2BC (+)-Negative battery terminal (-)
Fuel Injection No. 3: 2BD (+)-Negative battery terminal (-)
Fuel Injection No. 4: 2AZ (+)-Negative battery terminal (-)

Oscilloscope setting

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

Vehicle condition

Idle after warm-up

Fig 10: Screen Display - Fuel Injection Signal Waveform
Courtesy of MAZDA MOTORS CORP.

A/F sensor heater control signal

PCM terminals

2BG (+)-Negative battery terminal (-)

Oscilloscope setting

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

Vehicle condition

Idle after warm-up (no load)

Fig 11: Screen Display - A/F Sensor Heater Control Signal Waveform
Courtesy of MAZDA MOTORS CORP.

When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

• You smell fuel, burning insulation, or see smoke.

• Brakes feel soft, pull hard to one side, or make grinding noises.

• The engine overheats, stalls repeatedly, or misfires under load.

• You are missing required tools, torque specs, or safe lifting equipment.

• You are not confident in the next step or safety outcome.

Safety Warning

Inspection Using An Oscilloscope (Reference)

Use the Manual With the Right Hardware

When to See a Mechanic

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