Book a Car Diagnostic in Watford

£157.16

Average price for this repair in Watford in the last 30 days^

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 in Watford

We’ll come to you at home or work

RAC Mobile Mechanic in Watford

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.

Average cost of a vehicle diagnostic by car make^

The RAC charges a flat rate for the cost of a car diagnostic but prices may change due to inflation. According to RAC data, the average cost of a car diagnostic is £87.

Make	Average price
Ford	£105
Vauxhall	£105
Volkswagen	£105
Peugeot	£104
Mercedes-Benz	£104
Nissan	£106
BMW	£107
Audi	£106
Renault	£104
Citroen	£104

^Average price quoted for RAC Mobile Mechanics from 01/01/25 to 31/03/25.

And it’s not just car diagnostics that we do in Watford

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

ACS Autowerks Limited

5.0/5

ACS AUTOWERKS first began in 1991 in West Drayton at a basic but functional workshop site. Many of you reading this may have been to see us at the original site and we thank you for your continued custom. For 17 years the company grew in knowledge, expertise and experience. Specialising in German Vehicles enabled our team to gain extensive knowledge in all areas of the German motor vehicle. Specialising heavily in BMW, Mercedes and Porsche has pushed ACS AUTOWERKS to the forefront of vehicle technology.Our bodyshop works to the highest standard and will treat every vehicle with the same respect and care as we do our own. We are able to offer repairs of any nature including insurance work. We also specialise in non fault accident claims and can assist you every step of the way to get your vehicle back on the road.

Unit 2 Chancerygate Industrial Centre, Horton Close, West Drayton, UB7 8EB

Hertfordshire Vehicle Services

4.7/5

Fast, professional and reliable service for the motorists of Hatfield, Welwyn Garden City and surrounding areas. Mechanical repairs and servicing undertaken on all makes & models of cars and light commercials. Diagnostics services also available, with the latest up to date equipment on the market alongside the general services we also specialise in DPF. WE WELCOME PRIVATE, FLEETS, TAXIS AND TRADE CUSTOMERS When it comes to looking after your car, look no further than HVS - our commitment to customer service makes us the obvious choice.

21 Fiddle Bridge Lane, Hatfield, AL100SP

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

Nash Mills MOT & Service Centre

3.8/5

At Nash Mills we are a young and progressive company located on the boundaries of Hemel Hempstead and further afield, such as in - St. Albans - Watford - Hatfield - Berkhamsted -Kings Langley We've been trading in the local Hertfordshire area since September 2013 and we have an excellent reputation for being one of the friendliest and most reliable garages in the county. Our, team combines 60 years of trade experience to deliver a complete range of repair and services for all make cars and vans. We carry all the latest diagnostics equipment, so we're able to diagnose all sorts of faults, as well as carrying out the more common repair types, such as: - Servicing - Mots - Engine diagnostics - Repairs When you need reliable commercial and regular vehicle services in and around Hertfordshire get in touch with Nash Mills MOT & Service centre on whocanfixmycar.com! At Eurorepar Car Service, we’re all about keeping you and your car moving with confidence. As a trusted network of local garages, we provide high-quality car maintenance and repairs tailored to your needs – all at competitive prices. With our exclusive Brakes for Life program and a 2-year parts and labour warranty, you can drive away knowing you’re covered for the long haul.* Ask your Eurorepar Car Service Centre to fit Eurorepar branded parts to qualify. Claims under the 2-year parts and labour warranty must be made at a Eurorepar Car Service Centre. Discover expert care, unbeatable value, and peace of mind – all under one roof. Ready to experience the Eurorepar difference? Request a quote or give us a call today! *Terms and conditions apply.

Nash Mills Mot And Service Centre, Rear Of - 194A Belswains Lane, Hemel Hempstead, HP39XA

Halt Motor Company

3.6/5

David Bux started Halt Motor Company in 1979 and it is now a well-established family business, with sons James and Charles now running the workshop full-time. HMC has been specialising in quality used cars since 1984 and all aspects of after-sales, including servicing, repairs and MOTs. As a proffesional car care centre, we have the latest equipment, which allows our qualified mechanics to diagnose any problems quickly. We have recently invested in more diagnostic equipment that will help us to rectify any problems you may have with your car more efficiently.

Unit 1, Hurricane Trading Estate, London, NW9 5QW

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.