Car Diagnostics | Book a Car Diagnostic for your Mercedes| RAC

Trustpilot rating for all RAC Mobile Mechanics.

Why choose the RAC for a car diagnostic?

At the RAC, we've got over 125 years' experience helping UK drivers. We have the skills and knowledge to keep your vehicle running.

Plus, with RAC Mobile Mechanics, you can avoid the hassle of taking your vehicle to a garage when you need a repair. We’ll come to you, at your home or work.

Close up of an RAC Mobile Mechanic underneath a car

Our top pick for your Mercedes

Our top pick

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.

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.

Try one of our RAC Approved Garages

View all garages

Auto Motor Solutions

4.7/5

We are a Independant garage what pride ourselves on the high standards of our work and customer satisfaction. We are RAC approved garage and a SHELL oil stockist. We always use quality parts and provide free no obligation quotes. We also offer 4 Monthly Finance Payment Plan at 0% interest. All work is considered and can be quoted for from standard services to engine rebuilds.

33 Wiltshire Road, Hull, HU46PA

Awan Auto Tec

4.7/5

Awan Auto Tec are an independently run garage based in Ardwick, Manchester, which has been established since 2016. We have a team of three very experienced, fully qualified City & Guilds and IMI approved technicians, who are also VOSA approved MOT testers. We carry out class 4 MOT’s in house as well as all forms of mechanical repairs, MOT repairs, maintenance work and servicing. We undertake work on all makes and models of vehicles, with no job being too big or too small. Our standard opening hours are 9-5 Monday to Friday and 9-2 on Saturday. With prior booking, Sunday appointments MAY be available. We also offer our customers a recovery at a reasonable price, with distance being no issue. We pride ourselves on the quality of our work and we use good quality original equipment parts, and we guarantee all of our work. Extra 10 % discount available upon proof of ID for; NHS staff Charity organisations Motor traders Armed forces members

Unit 1 Millgreen Street, Ardwick, Manchester, M126FB

RSC Ltd.

4.5/5

We have on site a fully equipped three ramp workshop. Our work shop philosophy is very old school, we will never carry out any work to your vehicle unless it is needed, always ask your permission to carry out any work up and above what has been agreed and do our utmost to give a fair and reasonable cost service at all times. As a result of this we have a loyal database of customers from Rickmansworth, Watford, Northwood, Hatch end, Bushy and surrounding area. We offer a wide variety of services at an extremely competitive rate especially when compared to the main dealers, these include: servicing, repairs, bodywork, tracking, tyres, air conditioning re gasses, clutches, brakes, exhausts, car audio and alarms.

Oxhey Drive, South Oxhey, Watford, WD197SE

Monster Gear Garage

4.6/5

We are an independent 5 star garage with high experienced technicians that will take care of your vehicle, we cover a wide range of repairs like: MOT repairs Servicing Air Con Regas Air Con Recharge Brakes Clutches Timing belt / chain replacements Welding Diagnostics Engine repairs / replacement Drive in with no appointment. If you wish to wait while your car is being repaired we have a luxury waiting area with TV, Wi-Fi and free hot drinks. Our garage is a comfortable place for you and your vehicle.

Bridge Road Ind Est, Unit 16 - 18, Bristol, BS154TA

PJ Automotive Ltd

5.0/5

We are an RAC Approved Garage carrying out work on all types of vehicles including commercial vehicles to 5 ton. We can MOT class 4, 5 and 7 vehicles. We specialise in German brand vehicles (BMW, Mini, Audi, Mercedes). We can however carry out work on any make.

Mount Pleasant, Hanley, Stoke On Trent, ST14AY

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.