Operation CHARM: Car repair manuals for everyone.

Oscilloscope Patterns and Waveforms

Inspection Using An Oscilloscope (Reference)

Fan control module (No.1) signal




PCM terminals
- 1AE (+) - body ground (-)

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

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

HO2S (front) heater control signal




PCM terminals
- 2C (+) - body ground (-)

Oscilloscope setting
- 2 V/DIV (Y), 20 ms/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
- 2 V/DIV (Y), 100 ms/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
- 2 V/DIV (Y), 5 ms/DIV (X), DC range

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)

Wastegate control solenoid valve signal




PCM terminals
- 2AA (+) - body ground (-)

Oscilloscope setting
- 20 V/DIV (Y), 20 ms/DIV (X), DC range

Vehicle condition
- Ignition switch to the ON position

Purge control signal




PCM terminals
- 2AB (+) - body ground (-)

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

Vehicle condition
- Engine speed is 2,000 rpm

OCV signal




PCM terminals
- 2AF (+) body ground (-)

Oscilloscope setting
- 2-5 V/DIV (Y), 1 ms/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
- 2A1 (+) - body ground (-)

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

Vehicle condition
- Idle after warm up (engine speed approx. 650 rpm, no load)

Generator output voltage signal




PCM terminals
- 2AJ (+) - body ground (-)

Oscilloscope setting
- 2 V/DIV (Y), 1 ms/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 (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 (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
- 10 V/DIV (Y), 20 ms/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, No.4: 2BG (+) - body ground (-)
- Fuel injection No.2, No.3: 2BH (+) - body ground (-)

Oscilloscope setting
- 20 V/DIV (Y), 400 micro seconds/DIV (X), DC range

Vehicle condition
- Idle after warm up (no load, P/S off, A/C off)