Engine management light
An amber engine light can mean anything from a loose fuel cap to a failing sensor or misfire. If it is flashing, ease off and get it checked straight away: that usually means a misfire that can damage the catalytic converter.
Vehicle diagnostics · Wimborne, Dorset
Vehicle diagnostics & fault finding
Warning light on? We read every system with dealer-level equipment, confirm the cause and tell you what it takes to fix.
4.9 216 Google reviews
Mon–Fri 8.30am–5pm
About our diagnostics
Find the fault first, then fix it
Technicians today face more technology and complexity every time a car comes in for a repair or service. A modern car can have dozens of control units and hundreds of possible fault codes, covering the engine, transmission, exhaust and emissions, brakes and every other major system, as well as performance issues with the fuel injectors, air flow, coolant, ignition and throttle.
Only specialist diagnostic equipment can read and make sense of those codes. Ours covers a wide range of manufacturers and gives us dealer-level access on the makes we specialise in, so our technicians have as much information as a main dealer. That lets us offer a full diagnostic service to a high standard on performance cars and everyday vehicles alike.
A fault code is the start of the job, not the answer. Where possible we physically inspect and test the part the system has highlighted before replacing anything, so you don't pay for parts you didn't need. Call us to discuss getting your car plugged in.
How it works
How we diagnose your car
Plugging in is the quick part. Finding the cause takes method. This is what happens when your car comes in.
- 1
Tell us the symptoms
When it happens, how often, hot or cold, at what speed. A good description narrows the search before the car is even plugged in.
- 2
Full system scan
We connect our diagnostic equipment and read every control unit, not just the engine: gearbox, ABS, airbags, body electrics and driver assistance systems.
- 3
Read the live data
Fault codes say where to look, not what has failed. We study live data and the conditions recorded when the fault was logged to see what the car was doing at the time.
- 4
Confirm with a physical check
Where possible we inspect and test the part the system has pointed at, so you only pay to replace what is actually faulty.
- 5
Explain and agree
We tell you what we found, what it will take to put right and what it will cost. Nothing is done without your go-ahead.
- 6
Fix, clear and road test
Once the repair is done we clear the codes, carry out any coding or adaptation the new part needs and road test the car to make sure the fault has gone.
Main dealer equipment
Dealer-level diagnostics, local garage prices
Our equipment gives dealer-level access on the makes we specialise in, as well as commercial vehicles. That means we are not limited to the generic engine codes a basic code reader shows. We can:
- Read and clear manufacturer-specific codes in every module
- View live data and the conditions recorded when a fault was logged
- Code and adapt replacement parts to the car
- Track down intermittent faults other garages have missed
Diagnosing a van or a motorhome? See our van servicing and motorhome and campervan servicing.
Signs you need it
When to book a diagnostic check
Any of these means the car has logged a fault or is about to. The sooner it is read, the cheaper it usually is to fix.
Limp mode & lost power
The car suddenly has little power, won't rev or holds one gear. The engine or gearbox has protected itself from a fault, and the stored codes tell us why.
DPF, EGR & AdBlue warnings
Diesels that do mostly short journeys can clog the DPF, stick the EGR valve or throw AdBlue faults. We find which it is, then clean, regenerate or replace as needed.
ABS, airbag & stability lights
Safety system warnings should never be ignored. A wheel speed sensor, a seat connector or a failing module can all be the cause, and only a full scan tells you which.
Jerky gearbox or poor shifting
Judder, harsh changes or a gearbox warning. Sometimes it is worn fluid that a gearbox oil service will sort; sometimes there is a fault to fix first.
Intermittent electrical faults
Windows, central locking, lights, infotainment or a battery that keeps going flat. The faults that come and go are the hardest to find, and the ones we're best equipped for.
Makes we diagnose
Makes and vehicles we diagnose
- Audi
- Dealer-level access across the range, including RS and R8
- BMW
- Full BMW fault-code access across every module
- Mercedes-Benz
- Mercedes-specific fault codes, cars and vans
- Porsche
- Engine, gearbox and chassis systems
- Volkswagen
- Full VAG protocol access, coding and programming
- Volvo
- Engine, gearbox and body systems
- Vans & motorhomes
- Commercial vehicles and motorhome base vehicles
- Other makes
- Our equipment covers a wide range of other manufacturers too
Driving a performance Audi? See our Audi RS and R8 servicing. Thinking about more power once the car is healthy? Ask about ECU remapping.
Book your diagnostics
Vehicle diagnostics across Dorset & Hampshire
Our workshop is on Woolsbridge Industrial Estate at Three Legged Cross, near Wimborne, an easy run from Verwood, Ferndown, Ringwood, Bournemouth, Poole, Christchurch, Salisbury and the New Forest. Tell us the symptoms when you book and we'll make sure the right time is set aside.
Tell us what you need using the form and we'll call or text to agree a time. Prefer to talk? Call 01202 283359.
- Wimborne
- Ferndown
- Verwood
- West Moors
- Ringwood
- Bournemouth
- Poole
- Christchurch
- New Forest
Vehicle diagnostics FAQs
Can't I just use a cheap code reader?
A basic code reader only talks to the engine and gives you a generic code. It can't see the gearbox, ABS, airbag or body modules, can't show manufacturer-specific codes and can't code new parts. It also can't tell you why a code was set. That takes live data, experience and a physical check.
How much does a diagnostic check cost?
It depends on the car and the fault: a warning light with a clear cause is quicker to find than an intermittent electrical fault. Call us on 01202 283359 with your registration and the symptoms and we'll give you a price before we start.
Can I keep driving with the engine light on?
If the light is steady and the car drives normally, it is usually safe to drive to us, but book it in soon. If the light is flashing, the car is losing power or a red warning is showing, stop as soon as it is safe and call us.
Will clearing the fault code fix the problem?
No. Clearing a code only switches the light off. If the cause is still there, the code comes back, and in the meantime the fault can get worse. We find and fix the cause, then clear the code.
Will an engine warning light fail the MOT?
An engine management light that stays on is an MOT failure. If your MOT is due and a warning light is showing, book diagnostics first. You can book an MOT alongside a service or repair with us.
Do you diagnose all makes?
Our equipment covers a wide range of manufacturers. We have dealer-level access on the makes we specialise in: Audi, BMW, Mercedes-Benz, Porsche, Volkswagen and Volvo, as well as commercial vehicles. If you drive something else, call us and ask.
Is a diagnostic check part of a service?
Yes. Our services include a full diagnostic health check, so stored faults are picked up even before you notice a symptom. See our vehicle servicing for what each service includes.
Can you fix the fault once you have found it?
Yes. Once we have found the fault we can put it right, whether that is a gearbox oil change for jerky automatic shifts, walnut blasting for a misfiring direct-injection engine, or a full repair.
What our customers say
4.9Excellent · 216 Google reviewsTim SmithApril 2026 · Google review
As a nervous user of garages (due to past poor experiences), I was pleasantly surprised about the high level of service Rob Lang provided with our Mk6 Golf GTD, which wouldn't start, and was marooned on our driveway. He had it recovered to his premises within hours, and his technician diagnosed and solved several electrical problems, plus he gave it a full service and MOT (and valet). It now drives like when it was new and so will be reprieved. Rob then delivered the car to our house because we couldn't collect it for several days more. We can't thank him enough. His prices are fair and much better than a main dealer I suspect (and very importantly he kept us in the loop).
Ken HowesMarch 2026 · Google review
What a breath of fresh air! Having a problem with Audi RS6 suspension and when I called Rob Lang he booked me in same day to investigate. They identified the problem and also gave the car a good general inspection while it was up on the lift. Super friendly, very knowledgeable and I will be happy to get future routine servicing done by Langs from now on.
Tim LoganMarch 2026 · Google review
Amazing service, from start to finish the team were professional and explained everything. The knowledge and speed were second to none. Our car was fixed, serviced and unexpectedly cleaned within the timeframe quoted. They are not local to me but happy to travel for an excellent experience.
Martin OlliverMarch 2026 · Google review
Having just purchased an Iveco Daily van that had a few issues that needed to be rectified, I used an Iveco dealership who surprisingly did not completely fix the problems. I met Rob and his team of experienced engineers and was extremely impressed by their knowledge and expertise. They identified the cause of all the outstanding problems. This is a company who know what they are doing, and their customer service skills are top-notch.
Danny CoombsApril 2026 · Google review
Got my car fully serviced yesterday, and was pleased with the thorough detail and information the team gave me. Nice office, clean unit and overall welcoming experience.
Steven KingMarch 2026 · Google review
You cannot possibly go wrong by fully relying on their advice and guidance, with work that is second to none. Rob is knowledgeable and kind, with this pervading through all the staff. I was in a really tight spot with poor workmanship from another company; this was sorted out quickly and efficiently and everything made perfect. I cannot rate this company highly enough.
Colin DeanMarch 2026 · Google review
Fantastic team, top quality work at a great price - would definitely recommend.
Lorraine LloydFebruary 2026 · Google review
I was recommended Langs and so glad they did. Amazing service where staff take the time to explain the work carried out. I highly recommend. Thank you Langs for a great experience.
Lisa HarlandMarch 2026 · Google review
Thanks so much for repairing my car Rob. Always first class service and know my car is in the best hands with you and the team there - would highly recommend.
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