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AV-SCANNER / Accessory guides / Diagnostic
This guide equips motorists and working mechanics with the knowledge to use a compression sensor with an oscilloscope to measure cranking compression without removing spark plugs or injectors. It covers sensor types, selection criteria, safe connection to the scope, and a full step-by-step procedure for capturing and interpreting compression waveforms. Readers will learn to read results with worked examples, apply the technique to real diagnostic jobs, avoid common mistakes, and maintain and calibrate the sensor. By the end, they will be able to perform efficient, non-intrusive compression tests and know when to escalate to a professional.
Guidance is general and covers many makes. Exact procedures and values vary by model, so confirm them in the factory service information for your vehicle.
Download all 11 sections as a branded PDF to use in the workshop.
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