FAQs
Also: see our visual index of warning lights and what they mean here
Mobile vehicle diagnostics is the process of professionally scanning and interpreting a vehicle’s fault data at the customer’s location, rather than at a garage or dealership. Using dealer-level diagnostic equipment, faults are identified, explained, and prioritised so informed decisions can be made before repairs are authorised.
A diagnostic scan reads data from the vehicle’s control modules (engine, emissions, fuel, electrical systems and more). It identifies fault codes, system errors, communication issues, and abnormal readings. Importantly, it helps determine why a warning light has appeared, not just that one exists.
Not always. A warning light indicates that a system has detected an abnormal value, but it does not automatically mean a serious fault. Some issues are urgent, while others can be monitored or scheduled. Diagnostics is the only reliable way to know which category a fault falls into.
It depends on the fault. Some warning lights indicate non-critical issues, while others may affect safety or emissions compliance. A diagnostic assessment determines whether the vehicle can remain in use, should be monitored, or requires immediate attention.
Yes. Accurate diagnostics prevents unnecessary part replacement, repeat garage visits, and misdiagnosis. Many customers discover that issues are less serious or less urgent than initially feared, allowing them to plan repairs instead of reacting under pressure.
No. Fault codes indicate where a problem has been detected, not which part must be replaced. The same fault code can be caused by sensors, wiring, software issues, or mechanical wear. Diagnostics helps identify the root cause, not just the symptom.
No. Fault Fixer provides independent diagnostics only. This ensures advice is unbiased, with no incentive to upsell repairs. Customers are free to use any garage, dealer, or fleet provider for remedial work.
Yes. All findings are provided in a clear diagnostic report that can be shared with independent garages, main dealers, fleet maintenance providers, or used simply to inform your own decision-making.
Absolutely. Businesses and fleet operators use mobile diagnostics to reduce downtime, prioritise repairs and avoid unnecessary off-road time. Diagnostics allows informed decisions about whether vehicles can remain in service or require immediate attention.
Mobile diagnostics is recommended when:
• A warning light appears
• A vehicle enters limp mode
• A repair quote feels uncertain
• You want a second opinion
• A vehicle is needed daily
• A fleet vehicle requires rapid assessment
If the question is “Do we need to fix this now?” diagnostics is the answer.
Yes. Diagnostics and inspections before purchase help identify upcoming costs, hidden faults and true vehicle condition. This is especially valuable for professional buyers, traders, and anyone negotiating price.
Garages often focus on repair rather than explanation. Mobile diagnostics allows faults to be identified before repair discussions begin, giving customers clarity and control over what happens next, without pressure or disruption.
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To book your inspection please call us on 0333 366 0155, or complete the form below