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AV-SCANNER / IMMO guides / Modules
This guide explains why a replacement engine control unit (ECU) must be matched to the vehicle's immobiliser system before the engine will start, and it sets out the lawful routes available to a motorist or their technician. It covers how the immobiliser and ECU handshake works, the ownership documents you must have ready, how to choose between a franchised dealer and a registered automotive locksmith, and what a professional matching session actually involves. By the end you will be able to plan the job, verify the result with confidence, recognise common problems and scams, and take steps that prevent a repeat failure.
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 12 sections as a branded PDF to use in the workshop.
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