How to hire
Match the specialist to the fault first. An auto electrician owns diagnostics, wiring traces, battery and charging faults, starter motors, alternators, lighting and module coding — the wiring and electrons rather than the oily bits. A general garage suits a service with an electrical sideline, while a main dealer suits warranty work and brand-new models with locked-down software. When you first enquire, give the make, model, year and registration, say which warning lights show, and say whether the fault is constant or comes and goes.
For hybrids and electric cars, ask about high-voltage competence specifically. IMI TechSafe recognition marks technicians qualified to work safely on electric, hybrid and other safety-critical systems, with ongoing training required to keep it [2]. The IMI Professional Register lets you search for a member or business by name and see what sits behind the claim [1]. Since no mandatory registration applies to the trade, a voluntary listing like this is the closest thing to a badge worth checking.
Check the business behind the van too. A limited company with years on the record is easier to trace than a name with no footprint, and a published workshop address tells you where the car will actually sit. Businesses signed up to The Motor Ombudsman's Service and Repair Code commit to open and fair dealing, and the ombudsman can step in when a complaint cannot be resolved [7]. Ask for public liability insurance detail and a local reference you could verify.
Describe the symptoms before anyone sets out: which lights show on the dash, what happens when you turn the key, what has already been tried, and a photo of the dashboard helps. Agree the diagnostic fee for the first hour and ask whether it comes off the final bill if you go ahead with the repair. For a mobile visit, say where the car is parked, whether there is room to work around it, and whether it starts at all.
Get the quote in writing with diagnostic time, parts and labour split out, and ask whether each part is new, genuine, pattern or reconditioned — the answer explains most price gaps. It should name any call-out or mobile fee, say whether VAT is added on top, and state the warranty on parts and labour separately. Treat an outlier far above or below the rest as a question rather than a bargain, and compare every quote on the same written scope.
At the end, keep the itemised invoice, the diagnostic or fault report naming what was tested and found, and the warranty terms for parts and labour. If the car has start-stop, check the new battery was registered to the car's management system. File everything with the service history — it matters at sale time. If the work goes wrong and the firm will not put it right, Citizens Advice sets out your consumer options [6].
Telford and Wrekin shapes the practical side. The leader works from a fixed workshop on Commercial Way in Oakengates, so you take the car to it during weekday hours; the runner-up works mobile from Trench Lock, so it takes the kit to you. Either way, say where the car sits and whether there is room to work around it when you first enquire. The council publishes a map of the car parks it manages across the borough, twenty-four of them free of charge [8], and its parking pages set out permits and enforcement [9] — handy if the car must sit somewhere public while you arrange the visit. In the Gorge at Ironbridge, which sits inside one of the borough's seven conservation areas [10], visitor traffic can make access slow, so agree the exact meeting point before a mobile visit.
A typical job runs in the same order whatever the fault. You send the symptoms in writing — make, model, year, registration, which lights show, whether the fault is constant or intermittent, and a photo of the dash. The firm replies with a diagnostic slot and fee; the test session follows, ending in a fault report naming what was tested and found. You then authorise the repair, or decline it and pay the diagnostic fee, before any parts are ordered. The work is done, and you leave with the itemised invoice, the report and the warranty terms filed together. Firms in The Motor Ombudsman's Service and Repair Code follow its dispute process if you later disagree [7].
On the quote itself, look for the labour basis alongside the split, each part named with its provenance, VAT shown inside or on top, any call-out or mobile fee, how long the price holds, and who will actually do the work. At sign-off, expect the fault report to show before-and-after readings or codes where the job allows, plus a short road-test note for faults that affect driving. Pay the balance when the paperwork is complete, and keep every message from the first enquiry in writing.
Pricing
As of autumn 2026, a car diagnostic test typically costs £80 to £120, with many drivers paying close to £99 [3]. A basic fault-code scan sits around £80 to £110, while in-depth electrical diagnostics with live system testing runs £150 to £250 or more, with luxury and performance cars at the top end for their specialist kit and longer sessions [3]. Always ask whether the quoted fee is deducted from the repair bill if you go ahead.
Beyond the diagnosis, published guides put simple electrical repairs from around £70 for brake lights, with an alternator replacement near £250 [4]. A replacement car battery costs £80 to £250 fitted, with fitting adding up to £40; start-stop cars need costlier AGM or EFB batteries that must be registered to the car's management system [5]. Neither Telford firm publishes set rates, so treat these as context for the quote, not a quote themselves.
What moves the price is mostly time and kit: intermittent faults that need hours of tracing cost more than a fault with a clear code, dealer-level software for premium badges adds to the bill, and a mobile visit can carry a call-out fee a workshop job avoids [3]. Start-stop battery type, awkward access to wiring, and parts choice between genuine, pattern and reconditioned all shift the total.
Ask whether VAT sits inside or on top of every figure, since published ranges do not always say [3] [4]. Get the scope in writing before work starts — exactly which tests, parts and making-good are included, and what changes the price if tracing uncovers worse wiring than expected. Agree payment stages and keep every quote, invoice and report together.
Job by job, the same pattern holds. A battery supply-and-fit turns on the battery type, with start-stop cars needing registered AGM or EFB units rather than conventional ones, plus access to the bay and any coding time [5]. An alternator or starter replacement turns on parts provenance — genuine, pattern or reconditioned — and on the labour time the access demands [4]. Warning-light diagnosis and wiring traces are sold as session time, where the depth of the trace and the need for dealer-level software on premium badges set the bill [3].
Red flags
Quotes a wiring repair without seeing the car or asking about the symptoms and warning lights first.
Starts replacing parts before any diagnostic test has named the fault.
Cannot name the qualification or recognition behind the person doing the work when asked.
Tackles high-voltage hybrid or electric systems with no EV qualification or TechSafe recognition to show [2].
Gives one fixed price with no split between diagnostic time, parts and labour.
Asks for full payment in cash before starting, with no written quote or terms.
Clears a warning light without explaining the fault or giving a written report of what was found.
Will not put the scope, price and warranty in writing before lifting a tool.