Oscilloscope Patterns and Waveforms

Inspection Using An Oscilloscope (Reference)

VSS signal

Oscilloscope Wave Form:

- PCM terminals: 10, 2M, 2N(+)-body ground(-)
- Oscilloscope setting: 1 V/DIV (Y), 10 minutes/DIV (X), DC range
- Vehicle condition: Drive the vehicle with approx. 10 km/h {6.2 mph}

Purge control signal




- PCM terminals: 2C(+)-body ground(-)
- Oscilloscope setting: 2 V/DIV (Y), 10 minutes/DIV (X), DC range
- Vehicle condition: Idle after warm up (no load, P/S off, A/C off)

OCV control signal




- PCM terminals: 2E(+)-body ground(-)
- Oscilloscope setting: 2 V/DIV (Y), 0.8 minutes/DIV (X), DC range.
- Vehicle condition: Idle after warm up (no load, P/S off, A/C off)

CMP sensor signal




- PCM terminals: 2S(+)-body ground(-)
- Oscilloscope setting: 1 V/DIV (Y), 25 minutes/DIV (X), DC range
- Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

CKP sensor signal




- PCM terminals: 2W(+)-body ground(-)
- Oscilloscope setting: 1 V/DIV (Y), 2.5 minutes/DIV (X), DC range
- Vehicle condition: Idle after warm up (no load, P/S off, A/C off)

HO2S (front) signal (California emission regulation applicable ATX model)




- PCM terminals: 2AD(+)-body ground(-)
- Oscilloscope setting: 0.1 V/DIV (Y), 400 minutes/DIV (X), DC range
- Vehicle condition: Idle after warm up (no load, P/S off, A/C off)

Generator field coil control signal




- PCM terminals: 2AI(+)-body ground(-)
- Oscilloscope setting: 0.5 V/DIV (Y), 1 minute/DIV (X), DC range
- Vehicle condition: Idle after warm up (no load, P/S off, A/C off)

Generator output voltage signal




- PCM terminals: 2AJ(+)-body ground(-)
- Oscilloscope setting: 2 V/DIV (Y), 2 minutes/DIV (X), DC range
- Vehicle condition: Idle after warm up (no load, P/S off, A/C off)

IGT1, IGT2, IGT3, IGT4 control signals




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

- Oscilloscope setting: 4 V/DIV (Y), 0.01 minute/DIV (X), DC range
- Vehicle condition: Idle after warm up (no load, P/S off, A/C off)

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: 4 V/DIV (Y), 10 minutes/DIV (X), DC range
- Vehicle condition: Idle after warm up (no load, P/S off, A/C off)

HO2S (rear) heater control




- PCM terminals: 2BE(+)-body ground(-)
- Oscilloscope setting: 2 V/DIV (Y), 1 second/DIV (X), DC range
- Vehicle condition: Idle (immediately after starting the engine)

HO2S (front) heater control




- PCM terminals: 2BG(+)-body ground(-)
- Oscilloscope setting: 2 V/DIV (Y), 500 minutes/DIV (X), DC range
- Vehicle condition: Idle (immediately after starting the engine)