ABS Repairs

ABS Repairs

Anti-Lock Breaking System (ABS) can be a costly repair to your car

A1 Diagnostics & ECU Repairs repair ABS Control Units and Pumps. We are ABS specialists in Cardiff and we can fault find and test faulty Anti-Lock Breaking Systems (ABS).

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Air Conditioning

Air Conditioning

Having the state of the art air conditioning unit, we offer Air Conditioning Servicing which includes:

  • Tracer pumped throughout the system to check for leaks
  • Freshener and antibacterial killer to remove and any bacterial from the system
  • Gas Refill



  • Oil to re-seal and lubricate the pipes and pump

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ECU Repairs

With over 30 years’ experience in the motor trade, we have serviced cars and commercial vehicles with some of the very first engine control units (ECUs). In that time, we have become an industry leader and specialist in ECU testing and repairs, offering the highest standard of work backed by excellent customer service from our garage workshop pictured below.

1234 ECU Repairs


We have the latest state-of-the-art technology that allows us to test ECUs and identify persistent faults, as well as finding the intermittent faults you may not be aware of.

We are able to test and repair all engine control units, including:


• Air bag ECUs

• Engine ECUs

• Dashboard ECUs

A fraction of the price of a new unit

ECU repairs at A1 Diagnostics are a fraction of the price of a new unit, and can help you make a big saving on the cost of going to the main dealer. We perform ECU testing and repairs on all major vehicle types, from family cars to vans and commercial vehicles.

We also hold a large number of ECU units and replacement parts in stock, and constantly update our range to meet our customers’ needs. That means in many cases, our ECU specialists can get you back on the road quickly without having to order parts in.

Book your car in with the ECU specialists

With years of experience, our professional technicians have the expertise to work on any ECU job, from small repairs to complete overhauls. Importantly, our pricing is completely transparent, so no hidden charges are added after the work is done. If we do identify any further faults when testing your ECU, you will be advised of the cost of the repair before we start the work.

Contact us to book your vehicle in with Cardiff’s best ECU repair specialists, please use the contact details below.

44 ECU Repairs


A1-Diagnostics and ECU Repairs
64 Sloper Road
CF11 8AB

Tel: (029 20) 220380
Fax: (029 20) 223172

Opening Times

Mon – Fri: 9:00am – 6:00pm
Sat: 9:00am – 1:00pm

Electrical Fault Findings

Electrical Fault Findings

Electrical fault service is offered, having all dealer level diagnostic tools and diagrams to hand, we are confident to face any fault finding job

Engine Control Units – vehicles are fitted with electronic management control units (ECU) and a multitude of sensors and wiring located throughout the engine.

We have the latest diagnostic equipment and circuit wiring schematics to pin point your fault with a quick and accurate diagnosis.

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Engines & Gearboxes

Engines & Gearboxes

We can provide engines and gearboxes for many makes of cars and vans, from our sister company Major Motor Services Ltd

We offer a full supply and fit service on low mileage imported engines, gearboxes and turbos with full 3, 6 or 12 month warranty on all parts.


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Immobiliser Repairs

Immobiliser Repairs

A1 Diagnostics and ECU repairs can fix your immobiliser repair problems quickly

When it comes to immobiliser bypass modules & immobiliser repair; this includes key coding and re-programming / cloning of remote controls. 99% of our business is carried out by post and we do not have to see your vehicle.

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A1 Diagnostics and ECU Repairs offer MOT packages for your family cars and light vehicles

MOT Approved Test station cardiffl MOTWe are a fully approved MOT Test Centre.

In addition to servicing & repairs we can also MOT your vehicle to approved VOSA standards.

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Regular car servicing, according to manufacturer’s recommendations, prolongs the life of your vehicle or fleet, and helps you plan maintenance before it becomes a necessity


  • Value for money
  • Quality workmanship
  • Free collection & delivery service
  • Air-conditioning service
  • Tyre and exhaust fitting centre
  • MOT

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