Inspection Using An Oscilloscope (Reference)

WARNING: This page is about a different car, the 2010 Mazda 3. However, it is still accessible from the selected car via links, so may be relevant.

Cooling fan control

PCM terminals

1R(+)-body ground(-)

Oscilloscope setting

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

Vehicle condition

Idle after warm up

Fig 1: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

APP sensor No. 2 signal

Accelerator pedal released

Fig 2: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

Accelerator pedal depressed

PCM terminals

1X(+)-body ground(-)

Oscilloscope setting

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

Vehicle condition

Switch the ignition to ON.

Fig 3: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

Purge control

PCM terminals

1BA(+)-body ground(-)

Oscilloscope setting

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

Vehicle condition

Idle after warm up

Fig 4: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

A/F sensor heater control

PCM terminals

2A(+)-body ground(-)

Oscilloscope setting

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

Vehicle condition

Idle (immediately after starting the engine)

Fig 5: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

HO2S heater control

PCM terminals

2B(+)-body ground(-)

Oscilloscope setting

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

Vehicle condition

Idle (immediately after starting the engine)

Fig 6: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

OCV control signal

PCM terminals

2E(+)-body ground(-)

Oscilloscope setting

2 V/DIV (Y), 0.8 ms/DIV (X), DC range

Vehicle condition

Idle after warm up

Fig 7: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

CMP signal

PCM terminals

2S(+)-body ground(-)

Oscilloscope setting

1 V/DIV (Y), 25 ms/DIV (X), DC range

Vehicle condition

Idle after warm up

Fig 8: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

CKP signal

PCM terminals

2W(+)-body ground(-)

Oscilloscope setting

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

Vehicle condition

Idle after warm up

Fig 9: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

IGT1, IGT2, IGT3, IGT4 control

PCM terminals

IGT1 (ignition coil No. 1): 2G(+)-body ground(-)
IGT2 (ignition coil No. 2): 2K(+)-body ground(-)
IGT3 (ignition coil No. 3): 2L(+)-body ground(-)
IGT4 (ignition coil No. 4): 2H(+)-body ground(-)

Oscilloscope setting

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

Vehicle condition

Idle after warm up

Fig 10: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

Generator field coil control

PCM terminals

2AA(+)-body ground(-)

Oscilloscope setting

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

Vehicle condition

Idle after warm up

Fig 11: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

Generator output voltage

PCM terminals

2AF(+)-body ground(-)

Oscilloscope setting

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

Vehicle condition

Idle after warm up

Fig 12: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.

Fuel injection (#1, #2, #3, #4) 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), 25 ms/DIV (X), DC range

Vehicle condition

Idle after warm up

Fig 13: Identifying Signal Waveform

Courtesy of MAZDA MOTORS CORP.