Car Diagnostics & Fault Finding
Warning lights, fault codes and electrical gremlins — diagnosed properly.
A warning light or an intermittent fault can be worrying, especially when you do not know how serious it is. At KNR Autos we use diagnostic equipment to read your vehicle’s fault codes and, just as importantly, investigate what is actually causing them.
Fault codes are a starting point, not the whole answer — so we combine the readings with hands-on checks to pinpoint the real problem. We then explain what we have found in plain English and talk through your options before any repair work is carried out.
Our diagnostics work
Engine Management Faults
Investigating engine management lights and faults to find out what is triggering them and why.
Warning Light Diagnosis
Reading and interpreting dashboard warning lights so you know what they mean and how serious they are.
ABS Diagnostics
Diagnosing anti-lock braking system (ABS) faults that affect braking and bring on the ABS warning light.
Airbag (SRS) Diagnostics
Checking airbag and SRS warning lights to identify faults in your vehicle’s safety systems.
Electrical Fault Finding
Tracing intermittent and tricky electrical faults — from non-working components to wiring issues.
Battery & Charging System Tests
Testing the battery, alternator and charging system to find the cause of starting or power problems.
DPF Fault Diagnosis
Diagnosing diesel particulate filter (DPF) faults and warning lights on diesel vehicles.
ECU Fault Code Reading
Reading stored fault codes from your vehicle’s ECU as the starting point for an accurate diagnosis.
When to book this service
Here are some common signs it is worth getting in touch. If in doubt, give us a call and we will happily talk it through.
- A warning light has appeared on your dashboard.
- The engine management (check engine) light is on or flashing.
- Your ABS or airbag warning light has come on.
- Something electrical has stopped working or behaves intermittently.
- The car is hard to start or the battery keeps going flat.
Why choose KNR Autos?
We keep things simple: clear advice, practical diagnostics and friendly, independent service.
- A local, independent garage based at Church Street Garage in Bishops Castle
- Practical, honest advice in plain English — no jargon
- Support for everyday drivers, families, vans and local businesses
- Servicing, repairs, diagnostics, MOT preparation and valeting in one place
- Clear communication before any work is carried out
- Friendly, convenient service close to home
You might also need
Repairs
Brakes, clutches, exhausts, suspension, batteries, tyres and general vehicle repairs done properly.
- General Vehicle Repairs
- Brakes & Brake Pads
- Clutch Replacement
MOT
Class 4 MOT testing, MOT preparation, MOT repairs and retests to keep your car road-legal.
- MOT Testing (Class 4)
- MOT Preparation
- MOT Repairs
Servicing
Car servicing, oil changes and vehicle health checks to keep your car running smoothly and reliably.
- Car Service
- Engine Oil Change
- Vehicle Health Check
Diagnostics FAQs
Can you check an engine warning light?
Yes. We can read the fault codes behind an engine management or check engine light and investigate what is triggering it, so you understand how serious it is and what needs doing.
What does a diagnostic check include?
We connect to your vehicle to read stored fault codes from the ECU, then carry out hands-on checks to confirm the cause. Fault codes point us in the right direction, but we always verify before recommending a repair.
Can you diagnose ABS or airbag warning lights?
We can. ABS and airbag (SRS) warning lights relate to important safety systems, so we can diagnose the faults behind them and advise you on what is needed.
Can you test battery and charging issues?
Yes. If your car is slow to start or the battery keeps going flat, we can test the battery, alternator and charging system to find the cause rather than just replacing parts.
Got a warning light or a fault?
Call KNR Autos or send a message and we'll help you get to the bottom of it.
Prefer to talk? Call 01588 638707