Operation CHARM: Car repair manuals for everyone.

Reference Waveform

Inspection of ECM and Its Circuits

CAUTION: ECM and its circuits can be checked by measuring voltage and pulse signal with special tool connected. It is strictly prohibited to connect voltmeter or ohmmeter to ECM with ECM connectors disconnected from it.

Reference waveform

NOTE:
- Waveform analysis is as follows.






- Waveform might change for measurement condition and vehicle spec.

Fuel Injector Signal






Measurement condition
- Engine: Idle speed after warm-up






Fuel Injector No.1 Signal and Ignition Coil No.1 Signal















Measurement condition
- Engine: Idle speed after warm-up






Fuel Injector No.2 Signal and Ignition Coil No.2 Signal















Measurement condition
- Engine: Idle speed after warm-up






Fuel Injector No.3 Signal and Ignition Coil No.3 Signal















Measurement condition
- Engine: Idle speed after warm-up






Fuel Injector No.4 Signal and Ignition Coil No.4 Signal















Measurement condition
- Engine: Idle speed after warm-up






Generator Control Signal and Generator Field Coil Monitor Signal









Measurement condition
- Engine: Idle speed after warm-up
- Lighting switch: OFF
- A/C switch: OFF
- Blower speed selector: OFF
- Rear defogger switch: OFF






Measurement condition
- Engine: Idle speed after warm-up
- Lighting switch: ON
- A/C switch: ON
Blower speed selector: 4th position or higher
- Rear defogger switch: ON






HO2S Signal and HO2S Heater Signal









Measurement condition
- Engine: Idle speed after warm-up






Measurement condition
- Engine: Racing after warm-up






Ignition Coil Signal






Measurement condition
- Engine: Idle speed after warm-up






MAF Sensor Signal






Measurement condition
- Engine: Idle speed after warm-up






A/F Sensor Heater Signal






Measurement condition
- Engine: Idle speed after warm-up






OCV Signal






Measurement condition
- Engine: Idle speed immediately after start-up






A/F Sensor Signal






Measurement condition
- Engine: Racing after warm-up






IMT Vacuum Solenoid Valve Signal






Measurement condition
- Engine: Racing after warm-up






Throttle Actuator Signal






Measurement condition
- Ignition switch: ON
- Accelerator pedal: Idle position






Measurement condition
- Ignition switch: ON
- Accelerator pedal: Fully depressed position






CKP Sensor Signal and CMP Sensor Signal









Measurement condition
- Engine: Idle speed after warm-up






Knock Sensor Signal






Measurement condition
- Engine: Running at 4,000 rpm after warmed up






Fuel Pump Relay Signal






Measurement condition
- Ignition switch: OFF -> ON -> START






IMRC Valve Motor Signal






Measurement condition
- Engine: When engine is cool and running at idle speed






Measurement condition
- Engine: Idle speed after warm-up






CAN Communication Signal









Measurement condition
- Engine: Stop
- Ignition switch: ON






EVAP Leak Detection Pump Signal






Measurement condition
- Ignition switch: ON






Measurement condition
- EVAP canister air (vent) valve: Operated (using active test of SUZUKI scan tool)