Car Diagnostics | Book a Car Diagnostic for your Mercedes

Trustpilot rating for all RAC Mobile Mechanics.

Why choose the RAC for a car diagnostic?

With RAC Mobile Mechanics, you can avoid the hassle of taking your vehicle to a garage. They can do a vehicle diagnostic check on your driveway, so you don't even need to leave the house.

When it comes to diagnosing issues with your vehicle, our friendly expert mechanics are here to help. We use state-of-the-art diagnostic equipment to accurately identify any problems, ensuring your vehicle runs smoothly and safely. The price includes the diagnostic service – no hidden costs. Just friendly, honest experts.

RAC Mobile Mechanics can carry out car diagnostics on popular Mercedes models such as A-Class, C-Class, GLC, E-Class, and EQA. This service is completed at your home or workplace, following Mercedes maintenance guidance and using OEM‑equivalent parts. You get clear pricing, real‑time updates and a convenient, no‑hassle experience.

Close up of an RAC Mobile Mechanic underneath a car

Our top pick for your Mercedes

We’ll come to you at home or work

RAC Mobile Mechanic for your Mercedes

CDRSD-703_SEO500_-_Location_Page_-_Top_Pick_-_800x450.webp

At the RAC, we’ve got over 125 years’ experience in offering complete peace of mind® to our members. We’re best known for our breakdown service. And now – our new RAC Mobile Mechanics are here to help make every day motoring easier. If you need a service or repair, they’ll come to you at your home or work.

Close up of an RAC Mobile Mechanic running a vehicle diagnostic check

Book a car diagnostic

Our mobile mechanics will spend up to 30 minutes checking your car for faults and talk you through any repairs you might need and give you a report for your records. There are various ways we can check for faults, which could include plugging in to check your car’s onboard engine management system.

OEM quality parts

We use original equipment manufacturer (OEM) standard parts, which means every new part will be the same standard and same quality as the original part it replaced.

Mechanics you can trust

Our mobile mechanics are friendly, honest, and backed by the RAC.

Book a repair

It’s easy to book a car repair online. We bring the garage to you with RAC Mobile Mechanics, or find a trusted local garage. Common repair jobs include:

Clutch Replacement

We diagnose and repair clutch issues – whether your clutch is heavy or slipping, or you’re having trouble changing gears.

Alternator repair

We check and correct alternator faults to keep your charging system running smoothly.

Oil change

Oil is vital to a healthy engine, so it’s important to change it regularly.

Brake pads & Discs

If your brakes are making noise or you’re noticing reduced stopping power, it’s likely time to replace your brake pads or discs.

And it’s not just car diagnostics that we do for your Mercedes

Mobile mechanics bring the garage to you, saving you the hassle of getting your car to a garage. If you need a service or repair, they’ll come to you at your home or work.

A close up of an RAC mobile mechanic looking under the hood of a car

Try one of our RAC Approved Garages

View all garages

Wincanton Motorsport Ltd

4.9/5

We are a well-established workshop which has built up a fantastic reputation within the local area, since we first opened our doors in 1994. We carry out repairs, maintenance work, servicing and Class 1, 2 and 4 MOT’s on motorcycles, cars, light commercials and fleets. In 2008 we expanded the company and moved into a large 4000 square feet unit which has 4 service bays and an MOT bay. Our team of 4 technicians are fully qualified and have many years of experience within this industry. RAC approved. We use the latest diagnostic equipment, and use good quality parts to ensure that your vehicle remains in top condition at all times. This also means that we will not invalidate any existing warranties on your vehicle. We endeavour to make your experience as smooth sailing as possible and so offer our customers a free collection and delivery service within 2 miles, the use of our courtesy vehicles (subject to availability) or the use of our comfortable waiting room which has Wi-Fi and refreshments. All work comes guaranteed.

Wincanton Motorsport Ltd, Unit 10, 11-12 Hopkins Court, Bennetts Field Trading Estate, Wincanton, BA9 9TD

Robinwood Autos

4.9/5

We are an independent garage who believe in putting the customer first. We have over 25 years experience in the motor trade and have vast knowledge of the industry. We believe in giving the customer all the information and allowing a 'no pressure' decision on what work you as the customer would like to have done. We offer competitive pricing and a friendly approach, you can rest safe in the knowledge you're in good hands. All work is guaranteed for 12 months

Robinwood Autos, Unit 11, Wallingfen Business Park, Newport, HU152RH

LA MOTORS & MOT

5.0/5

Welcome to LA Motors & Mot ltd - your trusted partner for car maintenance and repairs! At LA Motors & Mot , our dedicated team is committed to providing reliable and professional automotive services to our valued clients. We go above and beyond to exceed your expectations by employing skilled technicians, utilising state-of-the-art facilities, and adopting a customer-centric approach. As a full-service auto repair garage Corby, we have been proudly delivering top-quality automotive repairs and maintenance to our community for several years. Whether you are in need of basic services or more complex repairs, you can trust our team to deliver exceptional service of the highest quality. Why Us? With a combined experience of over 25 years in the automotive industry, our team at LA Motors & Mot ltd possesses the expertise and equipment to serve as your ideal one-stop shop for all your vehicle requirements. As a family-owned local business, we maintain an unwavering commitment to upholding the highest standards. Nothing leaves our shop unless it meets our stringent "above the bar" approach. Our name proudly displayed above the door signifies our dedication to treating our customers like family. When you choose LA Motors & Mot ltd, you can expect nothing less than honesty, professionalism and exceptional service. So, why wait? End your searches for ‘garage Corby’ with us today!

28 Main Street, Caldecott, LE168RS

Courtwood Car Services

4.2/5

Based in Uxbridge and established since 1978, Courtwoods are a family run company with a reputation for being reliable, friendly and professional. We are committed to excellent customer care and we continually work towards providing the best service for both you and your Courtwood Car Services is your local car clinic serving motorists in Uxbridge, Hillingdon, Middlesex and West London.We specialise in MoTs, servicing, all types of mechanical and electrical repairs, air-conditioning servicing and recharges on any make or model of car for private individuals or local Uxbridge based businesses.

Penfield Estate, 17 Lancaster Road, Uxbridge, UB8 1AP

Auto-Line MOT Centre

5.0/5

Here at Auto-Line M O T we offer high quality servicing and mechanical repairs. We carry out any repairs to industry standard service manual labor times. We also offer a free collection and delivery service and vehicle movement services, which are subject to availability. We are a small close-knit team of two technicians with over 30 years of experience between us. We have a real passion for what we do and carry out every single job, no matter how big or small, to the highest standards. Owner Oliver is fully licensed, insured and qualified in the following; DVSA registered Authorised Examiner and mot tester Automotive Refrigerant Handling (EC Level 3 Award (IMI Awards Ltd) Light Vehicle Maintenance and Repair Competence, Level 3 Diploma (IMI Awards Ltd) Light Vehicle Maintenance and Repair Principles, Level 2 Diploma (IMI Awards Ltd). Numerous product courses with Ford Numerous product course with jaguar land rover Numerous product courses with BMW Luke is a landrover master technician Very experienced with all makes and models as comes from and aftermarket background. Light Vehicle Maintenance and Repair Competence, Level 3 Diploma (IMI Awards Ltd)

Unit 17 British Waterways Yard, Shardlow, Derby, DE722HL

Frequently asked questions on car diagnostics

How much does it cost to diagnose a car problem?

The cost you pay can vary depending on the type of car and how complicated the diagnostic test. Check with your mechanic for a quote.

Is a car diagnostic test worth it?

Yes, a diagnostic test may save you a lot of money. It finds issues early before they become costly repairs. It can also keep your vehicle running efficiently and safely

Can I do a car diagnostic myself?

While you can buy a diagnostic tool, interpreting the results needs expertise. It’s best if you to have a professional mechanic perform the test.

How long does a car diagnostic test take?

Diagnostic tests take from 30 minutes to a few hours. This depends on what issues are being looked at.

What are common car diagnostic codes?

Common diagnostic trouble codes include:

P0300: Random/Multiple Cylinder Misfire Detected
P0420: Catalyst System Efficiency Below Threshold
P0171: System Too Lean (Bank 1)

These are general examples, so your car may have different codes. Always check with a mechanic so you get an accurate diagnosis.

Is a car diagnostic test necessary for a service?

Yes, they are. Regular diagnostics can help keep your car in good health. It makes sure that underlying issues are addressed quickly, so you can drive with peace of mind on the road.

Again, keep in mind that mechanics might have their own checklists. Chat with your mechanic to be sure that they address any specific issues you have.