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Fault codes read, then tested — the cause traced before a part is proposed

A stored code tells you where to look, not what has failed. We read the codes, then test the circuit or component behind them so you are quoted for the cause, not for a guess.

Diagnostic reader and cable on a workshop bench

Engine Diagnostics

Read, tested, then traced to the cause

A warning light is a starting point, not an answer. A stored code narrows the search to a circuit or a system; on its own it does not tell you which component has actually failed.

So we read the codes and then test. Live data is compared against the fault condition, circuits and sensors are checked with a meter, and the wiring is followed rather than assumed. Only once the cause is confirmed do we price a repair.

You get the finding in plain language: what was tested, what failed, what it affects and what we propose. If a fault is intermittent we will say so, and say what we would need to catch it in the act.

Codes read and interpreted
Live data checked against the fault
Circuits and sensors tested
Cause explained and a repair priced

What the job involves

Four points that cover the work, and the order it happens in.

Read, then testCodes are read first, then the circuit or component behind the fault is tested with a meter.

Live data, not guessesSensor readings are compared with the fault condition while the vehicle is running.

One cause, namedWe do not replace parts until a test has confirmed what has failed.

Explained plainlyYou get what was tested, what it means, and what we propose, in writing.

Pricing & approval

Diagnostic time is work

Diagnostic time is priced as work in its own right, because that is what it is: reading codes, testing circuits and confirming which part has failed. Whether it is absorbed into a repair depends on the job, and we tell you which applies before we start. If you decide not to go ahead, the diagnostic time remains payable — but you keep the finding, which is yours to use wherever you have the work done.

My light came on and then went off. Should I ignore it?: No. A code that has since cleared is usually still stored, and an intermittent fault is exactly the kind that returns at the worst moment. Bringing it in while the code is stored saves diagnostic time later.

Can you diagnose without the fault being present?: Sometimes. Stored codes and freeze-frame data often show the conditions when the fault occurred. If nothing is stored we will say so, and set out what we would need to catch it.

Will you tell me if the fault is not worth repairing?: Yes. If the cost of the repair does not make sense against the vehicle, we will say that rather than quote it anyway.

Workshop interior at the end of the working day

Next step

Book a diagnostic check

Describe what the vehicle is doing — the light, the noise, when it happens — and we will say what we would test and what it involves.

Book this in +44 7891 854060

Call the workshop: +44 7891 854060
Email an enquiry: support@selectcar.repair
Send us first: Make, model, year, mileage and what the vehicle is doing.