What Are Manufacturer Repair Methods? OEM Repair Explained

What is an OEM repair method?

An OEM repair method is the vehicle manufacturer's own documented instruction for repairing a specific area of a specific vehicle. It sets out which repair options are permitted, the materials and joining methods to use, the sequence of the work, and which components must be replaced rather than reused.

OEM stands for original equipment manufacturer. In the context of repair information the OEM is the vehicle manufacturer itself, so “OEM repair method”, “manufacturer repair method”, “OEM repair procedure” and “factory repair procedure” all describe the same thing: the document the people who designed and built the vehicle wrote about how it is to be put back together.

The important consequence is how narrow that document is. A method is written for one model, usually one model year and body style, and sometimes one market. Two cars that look identical on a forecourt can have different structural materials, different sectioning points and different post-repair requirements. That is why repair information is retrieved from the vehicle's identity rather than from its name — the same reason parts are, as our guide on finding parts by VIN or registration explains.

“OEM repair” has two meanings — check which one is meant

The phrase gets used loosely on estimates and in insurer correspondence, and the two meanings pull in different directions.

• Repairing to the manufacturer's method — the work follows the manufacturer's documented procedure for that vehicle: the permitted sectioning, the specified joining technique, the specified consumables, the required calibrations afterwards. This is about how the repair is carried out.
• Repairing with OEM parts — the components fitted come from the vehicle manufacturer's own supply network, or from the company that supplies them. This is about what goes onto the car, and it has its own vocabulary, covered in our guide to genuine, OEM, OES and aftermarket parts.

The two are independent. A repair can follow the manufacturer's method to the letter using an aftermarket panel, and it can use entirely genuine parts while departing from the method. Most repairs need both, because the method itself frequently specifies which components are replace-only — and when it does, the parts question is answered by the method rather than by preference. An estimate that says “OEM repair” without saying which meaning applies is an estimate that will generate a query later.

What a manufacturer repair method contains

The depth varies by manufacturer and by vehicle age, but a method for a body or structural repair on a modern vehicle will normally cover most of the following.

• The permitted repair options for the section — replace complete, section at a defined point, repair in situ, or replace-only with no repair permitted. This is the decision the rest of the document hangs on.
• The materials in the area and the handling rules for each — mild steel, high-strength and ultra-high-strength steels, aluminium, magnesium and composites each behave differently under heat and each have their own replacement rules.
• The joining methods and consumables specified — resistance spot welding, MIG or MAG welding, MIG brazing, self-piercing or blind rivets of a stated type and size, structural adhesive with stated cure requirements, and often the number and spacing of the joints.
• The sequence — the order of removal, preparation, fitting and finishing. On a bonded or riveted structure the order is not a convenience; getting it wrong can mean undoing finished work.
• Single-use and replace-only components — bolts, rivets, clips, adhesive, seals, and anything deformed or deployed in the impact. These are the lines that need to be on the parts order early.
• Measuring points and tolerances, where the manufacturer publishes them, so the structure can be checked before and after rather than assumed.
• Post-repair operations — driver-assistance calibration, system initialisation, high-voltage reinstatement, fault-code clearance and road test requirements.
• Technician safety requirements — high-voltage isolation on electric and hybrid vehicles, handling of pyrotechnic restraint components, and extraction or protection requirements for particular materials.

Repair method, repair manual, bulletin: the vocabulary

Several different documents get called “the method” in conversation. Knowing which one you actually need shortens the request considerably.

• Repair method / repair procedure — used interchangeably. The instruction for one defined operation on one vehicle.
• Body repair manual — the manufacturer's complete body-repair document set for a model: materials map, sectioning drawings, joining specifications and the individual methods.
• Workshop or service manual — the mechanical, electrical and maintenance equivalent, covering removal and refitting, torque figures and fluid specifications.
• Technical service bulletin — a correction, clarification or update issued after the manual was published. A bulletin can supersede the manual, which is why the manual alone is not always the current answer.
• Repair methods pack or method sheet — the subset printed or exported for one job and kept on the repair file.
• Researched or independent repair method — a method produced by a research body rather than by the manufacturer. Widely used in the UK, and not the same document (see below).

Manufacturer methods and researched methods are not the same document

A great deal of UK collision repair runs on repair methods supplied by Thatcham Research through its escribe portal, which Thatcham describes as “the UK's leading repair methods solution” and which gives insurance engineers, vehicle damage assessors and repairers access to “methods, recommendations, technical information, times, parts and advanced driver assistance system (ADAS) fitment information”. Thatcham states that escribe is “compliant with BS10125 standards”, and that access to vehicle manufacturer methods comes through its escribe Plus subscription. Its own methods are developed in its Repair Technology Centre, with safety-critical information and ADAS and electric-vehicle considerations highlighted.

So there are two distinct things in circulation. A researched method is produced independently, formatted consistently across marques, aligned to the British Standard and accepted by insurers — and for the volume models most bodyshops see every week, it is what the job is quoted and worked from. A manufacturer method is the primary source: the document written by the people who specified the structure.

The manufacturer's own document is the one worth chasing when the researched coverage runs out or will not settle the question:

• Low-volume, prestige and specialist vehicles, where research coverage is thinnest and the structures are least generic. These are also the vehicles whose genuine parts are hardest to obtain.
• Newly launched models, before independent research has been published for them.
• Imported and grey-market vehicles, where the UK-market document may not describe the car in front of you.
• Aluminium-intensive, bonded and composite structures, where a generic instruction is least useful and the cost of guessing is highest.
• Older vehicles and restoration work, where the only information that ever existed is the manufacturer's.
• Disputed or unusual repairs, where a file needs the primary source rather than a secondary one.

The types of vehicle repair a method governs

Repair information is not only a structural-bodywork subject, although that is where it is discussed most. On a modern vehicle it reaches across the whole job.

• Non-structural panel repair — dent removal, bolted and bonded outer skins, plastic bumper and trim repair.
• Structural replacement and sectioning — rails, sills, pillars, floor sections and roof. The method states whether you may cut at all, and if so exactly where.
• Bonded and riveted body structures — the rivet and adhesive specifications, the preparation, and the cure conditions.
• Glazing — bonded screens form part of the structure on many vehicles and frequently carry driver-assistance cameras.
• Mechanical and driveline work — removal and refitting sequences, torque figures and the components that must not be reused.
• Electrical and electronic reinstatement — harness repair rules, module replacement and coding, and restraint-system handling.
• High-voltage work on electric and hybrid vehicles — isolation procedure, battery handling and enclosure integrity after an impact.
• Post-repair calibration — the manufacturer's requirements for resetting cameras, radars and sensors, which we also support through ADAS and wheel alignment.

Why the method is the reference point for the whole job

A structural repair looks finished long before anyone can tell whether it will behave correctly. The method is the only record of what correct meant for that vehicle, which is why it ends up being the reference point for the repair, the estimate, the parts order and the file.

It is also embedded in how UK repair quality is assessed. BS 10125:2022, “Automotive services. Vehicle damage repair processes. Specification”, sets requirements covering vehicle preparation, the repair processes themselves, the reinstatement of vehicle systems, the competence of personnel, tools and equipment, parts and controlled consumables, process management and control, and complaints handling. It applies to vehicles up to 5 tonnes gross vehicle weight and excludes motorcycles and three-wheeled vehicles. BSI runs a Kitemark scheme against the standard, and work providers frequently look for it.

Competence sits alongside the information. Driver-assistance calibration in particular is treated as a distinct skill rather than part of general diagnostics: the Institute of the Motor Industry runs ADAS accreditation and its TechSafe recognition, developed with industry bodies including Thatcham Research. Having the manufacturer's calibration requirement and having someone able to carry it out are two separate requirements, and a repair needs both.

The method also matters to the vehicle's record. GOV.UK classifies an insurance write-off that “can be repaired following structural damage” as Category S, and one that “can be repaired following non-structural damage” as Category N; in both cases the vehicle may be used again “if it's repaired to a roadworthy condition”. Where a repair is structural, the manufacturer's method is the clearest available evidence of what that condition required.

And it determines the parts list. The replace-only items a method names are not optional, and they are often the longest-lead lines on the job — which is an argument for requesting the method at the same time as the estimate rather than after the strip-down. We source those lines too: see genuine body panels and genuine mechanical components.

Are independent garages entitled to manufacturer repair information?

Broadly yes, and from two directions in UK law. Neither makes the information free, and neither makes it easy to find — but the entitlement is real and worth knowing about.

• Type-approval law. Article 61 of retained Regulation (EU) 2018/858 requires manufacturers to give independent operators “unrestricted, standardised and non-discriminatory access to vehicle OBD information, diagnostic and other equipment, tools” together with the “complete references, and available downloads, of the applicable software and vehicle repair and maintenance information”, presented as “machine-readable and electronically processable datasets”.
• Competition law. The UK's Motor Vehicle Block Exemption Order applies from 1 June 2023, and the CMA's accompanying guidance (published 5 June 2023) explains that a restriction on an independent operator's ability to access repair and maintenance information, tools or training does not gain the benefit of the exemption, and that access must be given in a manner that does not disadvantage the independent operator compared with authorised repairers. The guidance lists “repair and maintenance procedures”, parts catalogues, fault codes, ADAS and battery-management software and activation codes among the things that count as repair and maintenance information.

What that leaves is a practical problem rather than a permissions problem. Manufacturers meet the obligation through their own technical-information portals, each with its own registration, access terms and coverage by market and model year. Older vehicles may sit outside the scope altogether, and information for some older models was never published electronically at all. The work is identifying which portal holds the vehicle, establishing which document applies to that exact build, and getting it into a form the technician in the bay can actually work from.

How to get the manufacturer repair method for a vehicle

1. Fix the vehicle's identity first. The VIN resolves the exact build — model year, body style, market and any running changes. A registration will get you there; the VIN gets you there without ambiguity.
2. Describe the repair area, not just the panel. “Nearside rear quarter, replacement at the manufacturer's sectioning point” leads to a different document than “nearside rear quarter, dent repair”.
3. Say what the repair touches. Sensors, cameras, bonded glass, restraint components, high-voltage cabling or a battery enclosure in or near the repair area each pull in additional procedures.
4. Send the estimate or photographs. The estimate shows what was authorised; photographs show what is actually in front of you. Together they stop the wrong document being supplied for the right vehicle.
5. Confirm the document matches your exact vehicle. Model year, body style and market variants all change the answer, and a method for the facelift is not a method for the pre-facelift car.
6. Check for a later bulletin. A technical service bulletin issued after the manual can supersede it, and it is the part most often missed.
7. Order the replace-only parts as soon as the method names them. Those lines set the key-to-key time more often than the labour does.
8. Keep the method on the job file. Which document was used, for which VIN, and on what date. That is what answers a question about the repair months later.

Not sure which document you need? Send the registration or VIN, the make, model and year, and a description of the repair area, and we will tell you what we can supply for that vehicle before anything is committed.

What REMCAM does

REMCAM Automotive Ltd is an independent, trade-only business. We source manufacturer repair information for the specific vehicle you are repairing: you send the vehicle identity and the repair area, we identify the correct repair documentation for that vehicle's exact specification and supply it to you. We describe the service, not the source — we make no claim of manufacturer partnership, approval or official access, we are not a training body, and we do not certify repairs. Where a manufacturer has not published information for a particular repair, we say so rather than substituting something generic.

Because the method usually names parts, most enquiries come to us as one request. Send the vehicle details through Request a Part, or see manufacturer repair methods for how the service works and what to send. For the services around a structural repair — recovery of a non-driveable vehicle, cover while the car is off the road — see bodyshop support. We supply the trade only; private owners should ask their garage or bodyshop to make the request.

Sources

• legislation.gov.uk — Regulation (EU) 2018/858, Article 61 (access to vehicle OBD and repair and maintenance information), as retained in UK law
• GOV.UK / CMA — Guidance on Motor Vehicle Agreements (Motor Vehicle Block Exemption Order), 5 June 2023
• BSI — BS 10125:2022 Automotive services. Vehicle damage repair processes. Specification
• BSI — BS 10125 BSI Kitemark for Vehicle Damage Repair
• Thatcham Research — escribe repair methods portal
• Thatcham Research — Vehicle Repair Methods
• Institute of the Motor Industry — IMI TechSafe (ADAS accreditation)
• GOV.UK — Scrapping your vehicle and insurance write-offs: insurance write-offs (Categories S and N)