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

JOHN HARRISON LOWDHAM LIMITED, Bosch Car Service

4.6/5

Welcome to John Harrison (Lowdham) Ltd - we're a family run business having been established at the same location since 1946, later being the first established Peugeot dealership in the country in 1975. We pride ourselves in customer care, with many awards over the years gained through offering the very best in customer service experiences from buying a vehicle in the sales department through to our aftersales. We thrive on repeat business, with industry leading preparation standards alongside our non-pressurised sales environment enjoyed by our customers over the last 70 years. We provide the complete range of new Peugeot's from cars through to vans, alongside a superb range of 70+ multi franchise used vehicles. Our team will take the stress out of buying a new car. All you have to do is choose the one that best suits you. Then, the team will help you select the best finance package, organise the admin and get any maintenance taken care of. If you have any questions along the way, we will be more than happy to help. We also extensive aftersales facilities with 'All Makes' Servicing, MOT's, Four Wheel Alignment and more alongside our in-house bodyshop offering minor repairs through to full body resprays.

Southwell Road, Lowdham, Nottingham, NG147DS

Precision Autos Ltd

5.0/5

Established in November 2022 we are a freshly set up automotive repair shop based in South Molton, North Devon. We undertake many different types of vehicle repair and have a vast array of equipment in order to accommodate most types of repair necessary to vehicles old and new! We have over 25 years of experience repairing, fault finding and modifying in all aspects, from bulb changes to engine rebuilds, rewiring to restoration, tyre puncture repair to race car preparation, from brake pad replacement to full brake upgrades. We like to offer a trustworthy and honest approach to car repair, often going beyond what is necessary to keep you safely on the road. We also like to show you and explain potential problems and what they may cause giving you choices for the cost conscious motorist. Tea and coffee is very much available, made to your liking! So whether you want a chat about a slight rattle, or to book in for the Precision treatment, we're here for you and your vehicle, on hand with a proper brew and a friendly service.

Precision Autos Ltd, Units 9 And 10 J Bucknell Way Pathfields Business Park, South Molton, EX363FU

Bayley's vehicle locksmiths ltd

4.9/5

Bayleys Vehicle Locksmiths are an experienced, reliable and skilled local business based in Hove, East Sussex. We cover the whole of Sussex, Surrey and Kent and offer a 24 hour emergency response. VEHICLE LOCKSMITHS – VEHICLE REPAIR – MOT AND SERVICING WE OFFER COMPLETE KEY CUTTING AND CODING FOR MOST VEHICLES, INCLUDING HGVS & LGVS. HAVE YOU LOST YOUR HGV KEY OR NEED A SPARE ONE? WE COVER THE WHOLE OF SUSSEX, SURREY, AND KENT AND OFFER A 24-HOUR EMERGENCY RESPONSE. WE PROVIDE A FULL CODING SERVICE– ECU CODING – BSI UNITS AND CIM UNITS. ALL DONE AT OUR WORKSHOP OR WE CAN COME TO YOU. We offer complete Key cutting and coding for most vehicles, including HGVs & LGVs. Our team of experts can get your car fixed up in no time, so you can get back to your busy schedule. We also offer MOT and servicing services, so if your vehicle is due for its annual check-up, give us a call! Our expert technicians are only a phone call away when you need them!

Unit 1 D, Cambridge Grove, Hove, BN33ED

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

Bismillah Garage Services Ltd

4.2/5

Bismillah Garage Services is a family business, well established and respected MOT & car service garage in Luton also supplying replacement automotive parts such as exhausts, brakes spark plugs, oil filters and tyres. We undertake car servicing and repairs that including computer diagnostics, brakes, clutches etc. Regular car servicing can extend the life of a vehicle considerably and can save money. We focus on providing an exceptional garage service with competitive pricing. We have been serving customers in the Luton for 15 years. We have an up-to-date, fully equipped test centre, with all the facilities to service and repair your vehicles. We have built a solid reputation in Luton for delivering high quality garage services tailor made to meet the needs of our clients. Much of our business comes from word of mouth and satisfied repeat customers.

2A Tudor Road, Luton, LU3 1RN

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.