Car Diagnostics in Wymondham
Cars, vans, hybrids and EVsA warning light or fault code tells you where to look, not what's broken. We test until we've found the actual cause, so you only pay to replace the part that's failed.
- We find the cause before anything is replaced
- An estimate before any repair starts
Example fault codes, and what's really behind them
| Code | What the reader says | What it can turn out to be |
|---|---|---|
| P0420 | Catalyst efficiency below threshold | A worn catalytic converter, a faulty oxygen sensor, or an exhaust leak |
| P0300 | Random or multiple misfire | Spark plugs, ignition coils, injectors, or an air leak |
| P0101 | Mass airflow sensor range | A dirty or failed sensor, or a split intake hose |
| P2002 | DPF efficiency below threshold | A blocked filter, or a faulty pressure sensor reading it wrongly |
For illustration purposes only
Why a code reader alone isn't a diagnosis
Codes vs causes
Plugging in a code reader takes a minute. It gives a code that points at a system: the exhaust, the ignition, the fuel supply. It rarely names the part that's failed.
That's where money gets wasted. A garage that replaces whatever the code suggests may fit a new catalytic converter when the real fault was a much cheaper sensor. We read the code, then test the parts it could be, and only recommend the repair once the tests agree.
What happens at a diagnostic appointment
Step by step
Some faults show up in five minutes, others take a couple of hours. Occasionally a fault can’t be pinned down in one visit, and if so we’ll tell you.
1. Tell us what you've noticed
When the light came on, any noises, smells or changes in how the car drives. It narrows the search.
2. We read and record the codes
Using our diagnostic equipment, including stored and pending codes.
3. We test to find the cause
Live data, component tests and a physical inspection, until we know which part has actually failed.
4. We explain before we repair
You get the cause in plain English and an estimate for the repair. Nothing is replaced until you've agreed.
Warning lights we're asked about most
Troubleshooting guide
Our troubleshooting guide explains the likely causes. If the light is red, stop somewhere safe and call us before driving on.
Car diagnostics questions
How much does a diagnostic check cost?
We charge a set fee for a diagnostic check, but depending on what’s wrong, it can be reduced. Call us and we’ll talk you through it.
If I go ahead with the repair, is the diagnostic fee reduced?
It can be. If we find the fault quickly and you have the repair done with us, we’ll often charge only a little extra labour rather than the full diagnostic fee.
How long does a diagnostic check take?
Anything from five minutes to a couple of hours, depending on the fault. Intermittent faults can take longer to track down.
Can I drive the car in with the warning light on?
If the light is amber, usually yes, but book in soon. If it’s red or flashing, or the car feels different to drive, stop somewhere safe and call us first.
Do you diagnose hybrid and electric vehicles?
Yes, we diagnose faults on hybrid and electric vehicles, except for problems with the high-voltage battery.
Will clearing the code fix it?
No. Clearing a code switches the light off, but if the fault is still there the light comes back. We only clear codes once the cause has been fixed.
Warning light on?
Book a diagnostic check and we'll find the actual cause before anything is replaced.