Car Diagnostics | Book a Car Diagnostic for your Citroen

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 Citroën models such as C3, C3 Aircross, C4, C5 Aircross, and Berlingo. This service is completed at your home or workplace, following Citroën 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 Citroen

We’ll come to you at home or work

RAC Mobile Mechanic for your Citroen

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 Citroen

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

Sahibs Auto Electric

4.0/5

We are London's go to centre for MOT, Servicing, Alternators, Starter Motors and Car Diagnostics. We pride ourselves in Car Electrics and are well renowned for are specialists in Car Alternators and Car Starter Motors. Established in 1980, we have nearly 40 years of trusted experience the industry.

3 Norbreck Parade, London, NW107HR

Pinewood Garage Ltd

4.5/5

We are a limited company garage based in Thatcham, Berkshire. Our garage of fully trained technicians with over 30 years of experience is highly equipped, enabling us to offer a comprehensive range of servicing and repairs for all makes and models of vehicle. We pride ourselves on our workmanship, delivering an outstanding level of customer service and providing value for money to our customers. When bringing your car to us, you can be sure to be receive knowledgeable, honest and friendly advice along with a prompt and high standard of service.

Pinewood Garage Ltd, Hermitage Road, Cold Ash, Thatcham, RG189JN

ZS Motors London Ltd

5.0/5

At ZS Motors London Ltd, we pride ourselves on delivering trusted, high-quality automotive services across Rainham (Essex) and east London. With years of experience in the motor trade, we specialise in MOT, engine rebuilds, servicing, diagnostics, and repairs for a wide range of makes and models. Our mission is simple to provide honest advice, reliable workmanship, and excellent customer service. Whether you’re buying your next car, maintaining your current one, or in need of emergency repairs, our expert team ensures your vehicle is always in safe hands. Based in Rainham (Essex) East London, we have built our reputation on transparency, integrity, and a commitment to keeping our customers on the road with confidence.

Unit 3 And 4 Blackwater Close, Fairview Industrial Park, Rainham, RM138UA

Eastlake Garage

4.7/5

We are a well-established company with two sites in the local area, which have been in operation since 1999. We are AA, RAC and GREEN FLAG certified and are able carry out their breakdown and repair work and warranty work, as well as being Trading Standards approved and members of the Motor Ombudsman adhering to their strict code of conduct at all times. We are also Afilliated with the IMI We can offer our customers a free vehicle collection and delivery service within 10 miles of the garages, and we also offer discounts to NHS and Emergency Service staff members upon valid photographic identification.

Gaens Quarry, Porthcawl Road, South Cornelly , Bridgend, CF334RN

Clutchmaster Automaster

4.9/5

Clutchmaster was established in May 2000 by Dave Willcocks. Since then he has offered a "Second to none" clutch replacement deal for both public and trade customers. Due to our huge buying power we have been able to structure our prices accordingly, passing on superb savings. This makes Clutchmaster the best deal on BRAND NEW clutch parts not only in the Southwest but we believe Nationwide!!

Automaster Longcombe Cross, Longcombe, Totnes, TQ96PL

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.