Diagnostics
A warning light is a symptom, not a diagnosis. We read the fault codes, test what they point at, and tell you in plain English what is actually wrong. £54, refunded against the repair.
Book this in
Diagnostics · price before we startNo obligation — we price it before anything is touched
Book your car in- Price
- £54Refunded against the repair
- Time
- 1 hourLonger faults quoted before we continue
- Output
- Plain EnglishWritten, not a code printout
- Covers
- All systemsEngine, ABS, airbag, transmission
A code is a clue, not an answer
Every fault code points at a circuit, not a component. A code for a lean mixture does not mean the sensor is faulty — it means the system measured something outside its expected range, and the cause could be a split hose, a leaking injector, a blocked filter or the sensor itself.
Reading a code takes two minutes and any code reader off the internet will do it. Working out which of the possible causes is the actual one is the job, and it is what the hour is for.
Why we refund it
The fee comes off the repair bill if you go ahead with the work. That is deliberate. It means we have no reason to find an expensive fault rather than the real one, and you are not paying twice for the same hour.
If the answer is that the fault is trivial, or that the car is not worth repairing, you have still had a proper answer for £54, which is cheaper than replacing parts until the light goes out.
What happens, step by step
Tell us what it does
When the light comes on, whether it clears, what the car feels like. That narrows it more than the code does.
Read the codes
All modules, not just the engine. Stored and pending faults, plus live data.
Test what they point at
Voltage, resistance, pressure or live readings depending on the system. This is the part that takes the hour.
Find the cause
The component that has actually failed, rather than the one the code names.
Explain it in writing
What is wrong, what it costs, what happens if you leave it. In plain English.
Refund against the repair
Go ahead with the work and the £54 comes off the bill.
What’s covered
Engine management
Misfires, lean and rich codes, sensors, actuators.
ABS & traction
Wheel speed sensors, modules, wiring.
Airbag / SRS
Faults and seat occupancy sensors.
Transmission
Automatic fault codes and adaption readings.
Live data
Readings while the engine runs, not just stored codes.
Electrical
Charging, starting, parasitic drain and earths.
DPF & emissions
Regeneration history and differential pressure.
Written answer
What it is, what it costs, and what happens if you wait.
Diagnostics questions
Can't you just plug it in and tell me?
We can read the code in two minutes, and it will tell you which circuit reported a fault. It will not tell you which component failed. That is the difference between a code reader and a diagnosis.
Is the £54 on top of the repair?
No. It comes off the repair bill if you go ahead with the work.
The light went off on its own. Do I still need to come in?
Probably worth it. A fault that clears itself is usually intermittent rather than cured, and the code is normally still stored even when the light is out.
Can you clear the light without fixing it?
We can, but we will not do it without telling you what it was. Clearing a code on a car with a real fault is how MOT emissions failures and worse problems happen.
What if you can't find it?
It happens occasionally with intermittent faults. We will tell you what we ruled out, what it is not, and we will not charge you for a second hour chasing the same thing.
Where we do this work
All work is carried out at the Torrington Avenue workshop. We collect across these areas.
Tell us the reg and what it’s doing
Same working day answer with a realistic price and the next free slot.