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.

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

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.

A customer tending to her garage with an RAC Mobile Mechanic in the background

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.

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

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

Portsoy Auto Services Limited

4.5/5

family run local business comprising of 4 highly qualified mechanics.we are based at portsoy aberdeenshire we are on call 24/7 for any motoring needs and recovery work,we pride ourselves on being one if not the chepest and most reliable garage in the local area and beyond. we cover all aspects of motor vehicle work including but not limited to....... mot preparation,welding,clutches,brakes,suspension,12v vehicle systems,diagnostics,ecu remapping,servicing. we offer an exclusive deal for our customers tailored to your individual needs. take advantage of our payment options we accept cash,credit/debit card apply/google pay we also offer a payment assist option. take a look on our website for further details www.portsoyauto.com

25 Seafield Terrace, Portsoy, AB452FB

Rowledge Garage

5.0/5

sed in Rowledge Surrey, Rowledge Garage provides a quality, reliable motor engineering service covering all garage operations from MOTs to car servicing and auto diagnostics. The garage offers free vehicle pick up and drop off to customers for your convenience, plus competitive pricing with a personal service.

5 The Square, Rowledge, Farnham, GU104AA

All Trans Autos Ltd, Bosch Car Service

5.0/5

All Trans Autos was started in August 1980 by Jill and Richard. We employed our first member of staff, Tony, in 1984 and we are proud that he is still in our employment. Over the past 34 years All Trans Autos has grown and today has 15 employees, ranging from fully qualified technicians to part time office staff. Each one is a valued member of the team and provides the excellent customer service for which the company is renowned. All Trans Autos prides itself on its fantastic training program. Even after 25 years Tony is still attending training to keep up to speed with the fast moving technology in today’s cars. We have trained four apprentices over the period and currently have our fifth apprentice who is in his first year of training. The husband and wife team of Jill and Richard provides an excellent atmosphere. They work along side their staff, giving the garage that family feel. Their children all help within the company, inputting their skills where required, although only one of them works full time, as the company’s fleet manager. In 2006 All Trans Autos moved to its present location – the same year in which we became a Bosch Car Service centre. In order to become a BCS certain criteria have to be met. To read more about this see our Bosch page. Today All Trans Autos is one of the largest independent garages in Colchester. We offer unlimited expertise and are able to deal with most makes to dealer level. We operate to standards beyond those that are expected even by Bosch, and we won their quality award in our first year. We were shortlisted down to the last three in the Independent Garage of the Year Award in 2008.

Unit 7 Moss Road, Stanway, Colchester, CO30LE

Service Garage MOT & Repair Centre

5.0/5

Service Garage has been trading for over 60 years, established in 1946 we provide an extensive range of motoring services for Southend-on-Sea and surrounding areas. We can offer free collection and delivery service. The services we provide include; MOT testing, servicing, repair, batteries, tyres, exhausts, punctures, air conditioning and diagnostic testing.

4 Towerfield Close, Shoeburyness, Southend-On-Sea, SS3 9QP

MK MOT & Service Centre

4.8/5

We are a local independent garage offering our customers all forms of mechanical repairs, servicing and MOT's. Business partners Mark and Craig have over 50 years' experience working on all makes and models of vehicles, with no job being too big or too small. We are members of the Institute of the Motor Industry (IMI) which should offer you peace of mind that we take great pride in our work as it ensures we remain up to date with all courses and techniques. We work out of a large workshop which has 4 ramps, including an MOT bay, and we have a large comfortable waiting area available for your use should you like to wait whilst we work on your car.

36 Barton Road, Eaton Ind Est, Milton Keynes, MK23LQ

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.