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Servicing pricesEngine Diagnostics · Warning Lights & Faults
Engine Diagnostics in High Wycombe
RH Automotive has full engine diagnostic equipment on site in High Wycombe, and a technician who interprets what it finds rather than just reading a code. If your engine warning light is on, or the car's running rough, misfiring or using more fuel than it should, we quote before we start.
- DVSA Approved MOT Centre
- Class 4 & Class 7
- All Makes & Models
- 25 Years in High Wycombe
- Free Retest
We quote before we start
Every diagnostic job is different, so we quote first. Call or book online and we'll tell you what's involved before we start.
Warning lights
What does my engine warning light mean?
A steady amber light means a fault has been logged and it's worth booking a check soon, but it's usually still safe to drive. A flashing light is different and means an active misfire, so stop driving as soon as it's safe to do so.
| Light behaviour | What it usually means | What to do |
|---|---|---|
| Steady amber | A fault has been logged by the engine management system | Book a diagnostic check soon; usually still safe to drive |
| Flashing amber | An active misfire, which can damage the catalytic converter if you keep driving | Stop driving as soon as it's safe to do so |
This is general guidance, not a diagnosis for your specific car. Other warning lights, such as oil pressure or temperature, are separate from the engine management light and mean something different. If you're not sure what you're seeing, call us and describe it.
Straight answers
Diagnostic questions we get asked
Is a diagnostic just plugging in a code reader?
No. A fault code points at a system, not a part, so reading the code is only the start. RH Automotive has full diagnostic equipment and a technician who interprets what it's actually telling us, rather than swapping parts until the light goes off.
That's the real difference between a proper diagnostic and a free code read at a parts shop: knowing what the code means for your specific car, not just what it says.
What are the signs I need a diagnostic check?
Warning lights, poor running, a misfire, rough idle, worse fuel economy, a car that won't start, or electrical faults that come and go. Any of these are worth a diagnostic check rather than guessing at the cause.
Can a diagnostic fix the problem straight away?
Not always. A diagnostic tells us what's wrong and often confirms it there and then, but some faults need further tests once you know where to look, or parts to be sourced before the repair can start. RH Automotive explains what we find and quotes for the fix before doing any further work.
Will you clear the fault code without fixing the fault?
No, not on its own. Clearing a code without fixing what caused it just means the light goes off until the same fault triggers it again, and it can mask a problem that's still there. RH Automotive fixes the cause, then clears the code as part of that.
Related services
Also at RH Automotive
Brakes & Suspension
Pads, discs and suspension work, inspected and quoted before any work.
Brakes and suspensionMOT Test
Class 4 and Class 7 MOTs, with a free retest within 10 working days.
MOT pricesCar Repairs
Not sure what's wrong? Start here for every repair we cover.
All repairsBook online
Tell us what you need and we’ll call you back to confirm a slot. It takes about a minute. Prefer to talk? Call 01494 471017.
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