Vehicle diagnostics reference with 200 practical guides

Choose a system below to browse 200 diagnostic guides. Start with the problem you recognise. You do not need to know which module is faulty. The guides explain what to record and what the test results may mean.

EV, Body Electronics and Instrument Fault Guides

Charging equipment and session problems, Battery measurements and assessment records, Heating, ventilation and climate controls, Lighting circuits and replacement lamps, Instrument displays and vehicle information.

Browse EV, body and instrument guides

Sensors, Starting and Electrical Testing Guides

Sensor measurements and interpretation, Starting requests and restart symptoms, Power distribution and protective circuits, Emissions controls and monitored conditions, Electrical test methods and their limits.

Browse sensor, starting and testing guides

Networks, Software and Commercial Vehicle Guides

Vehicle-network architecture and evidence, Software operations and configuration, Infotainment, reception and connectivity, Water exposure and recurring corrosion, Vans, conversions and working vehicles.

Browse network, software and van guides

ADAS, Transmission and Specialist Repair Guides

Driver assistance and calibration evidence, Transmission data and repair scope, EV thermal management and verification, Choosing and preparing module repair, Service history and post-repair evidence.

Browse ADAS, transmission and repair guides

Existing collections

Arrange an assessment

Use the vehicle and module finder to prepare your details, or contact AXION about the appropriate route. Workshop visits are by appointment in Didcot. UK-wide postal enquiries are welcome for suitable removed modules; confirm suitability before dispatch.

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Saved guides on this device

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