Modern cars monitor dozens of sensors. When values fall outside expected ranges, the engine control unit stores a fault code and may illuminate the check-engine or emissions warning lamp.
Does a light always mean a big repair?
No. A loose fuel cap can set a code; so can a failing sensor or catalyst efficiency issue. The code points technicians to tests — it is not a diagnosis on its own.
MOT relevance
Emissions-related faults can cause an MOT fail if smoke, MIL behaviour or readings are outside limits. Fixing underlying issues before the test avoids retests.
What we do
- Read and document codes across major modules where supported
- Interpret results against symptoms
- Advise on repairs and clear codes after rectification
Book a computer diagnostic check — see current diagnostic price. Phone 07895 859505 for urgent advice.
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