Car Diagnostics | Book a Car Diagnostic for your Subaru

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 Subaru

We’ll come to you at home or work

RAC Mobile Mechanic for your Subaru

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

For a limited time, get £50 off repairs over £150 when you book a diagnostic test. Offer ends 09/12/25, 09:00.^**
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.

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 Subaru

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

Witney Vehicle Repairs Ltd

4.6/5

Here at Witney Vehicle Repairs we have over 30+ years of experience, pride ourselves on our commitment to give the very best in car repairs, servicing, diagnostics, & customer satisfaction. Our pricing is very competitive with no hidden surprises, We look forward to earning your trust & gaining your custom. And now we are proud to announce we have become an RAC approved garage offering RAC inspections, repairs and other RAC products. Also we are part of the RMI & and trust my garage network, We are now offering a Shell / Forte vehicle service, parts & preventative solutions package please contact us for more information.

Witney Road, Standlake Business Park, Witney, OX297PR

LM MOTOR CLINIC

4.8/5

Welcome to LM Motor Clinic in Kilmarnock. We are a long-established well run Castrol Service Centre providing exceptional garage repair services all provided by fully qualified and experienced technicians at competitive prices. Based in Kilmarnock, whether you need servicing, repairs or even diagnostics we can help. Our technicians have over 30 years combined experience in the motor industry so you can always rely on LM Motor Clinic for first-class servicing and repairs. What We Can Offer: Car & Van Servicing & Repairs Tyres & Exhausts Clutch Replacements Diagnostics Oil Changes Breakdown Recovery Castrol service Centre Flexible Payment Options As well as the above we also provide our customers in Kilmarnock with the following, Fair and Friendly Service, Pick Up Drop Off Service & all our garage services are Competitively Priced making sure you get the best possible rate for your service. Find out how we can help you Quality Work Honest Pricing Exceptional Customer Service Complete Peace of Mind We Have the Lastest Diagnostics with Dealer Software. Voted Scottish Garage of the Year and Scottish Specialist Garage of the Year at the Scottish Garage awards

19 Dean Street, Kilmarnock, KA31DY

Darlington Mot Centre

4.9/5

Darlington Mot Centre Mot cars, vans , motor homes , motorbikes , trikes ,quads • Comfortable reception to wait in • Motorcycle class 1 and 2 only £25 • Class 4 cars and vans only £45 • Class 7 & motor homes up to 3.5ton only £50 • MOT's carried out up to 28 days before expiry - keep your original expiry date • Post card reminder service so you never forget your MOT again • Free re-test within 10 working days • No charge for head light adjustments We service and repair all makes of vehicles All makes serviced and repaired • Full and Interim service • Body shop repairs for those little scrapes, dings and re-sprays • Air-con new and old gasses repairs • Timing belts and engine repairs • Brake disks and pads • Exhaust and suspension • Tracking 4 wheel alignment • Tyres new and part worn • Batteries, starters and alternators • Diagnostics and engine management systems • Clutches and gear boxes

Darlington Mot Centre, 410 Whessoe Road, Darlington, DL3 0RP

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

Acton Service Centre

4.2/5

Acton Service Centre came under new management in 2012. A family run business that prides itself in offering excellent customer service and professional workmanship. Our highly trained engineers and technicians are committed to providing you with the solution to all your motoring needs. Based in Acton just off the A406, our modern reception and viewing area has been newly designed for the comfort of our large base of loyal customers.

17-18 The Broadway, Gunnersbury Lane, Acton, W38HR

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.