Parts identification, done right
In-depth, practical writing on finding the exact genuine part — by VIN, from the official manufacturer catalogs. Written by the VINsearch editorial team.
EV batteries: repair, module replacement and the passport that arrives in 2027
The default answer to a failed traction battery has been to quote a whole pack, and the quote is frequently large enough to write the car off. That default is starting to break, partly because module-level repair is becoming practical and partly because regulation is about to make what is inside a pack far more visible.
Parts sourcingThe Chinese brands are already in your bay: identifying parts when the badge is new to you
A workshop that had never seen a Chery in 2022 now books three a month. The cars are not difficult. What catches people out is that the habits built over twenty years of German and Japanese work do not transfer cleanly, and the sub-brand structure hides which catalog you actually need.
AftersalesRight to repair and the data question: what an independent workshop can actually get
Right to repair is discussed as though it were one law and one victory. For a workshop it is neither. It is a slow, uneven expansion of access to specific kinds of manufacturer data, and the part that decides whether you can quote a job today is usually not the part making headlines.
Workshop how-toOil and fluid specifications by VIN: why the approval matters more than the viscosity
Two bottles both labelled 5W-30 can be entirely different oils, and pouring the wrong one into a modern engine can block a particulate filter or wear a camshaft. Viscosity is the number everyone quotes. The manufacturer approval is the part that decides whether the oil belongs in that engine.
Diagnostics and repairDiesel injectors: classification codes, copper washers and the job that must be finished properly
A common rail injector is a precision device manufactured to tolerances so tight that each one leaves the factory with its own correction code. Fit a set without entering those codes and the engine runs, badly, in a way that looks like a mechanical fault and is really an unfinished job.
Collision and bodyAirbag and SRS parts by VIN: the components you cannot guess at
Every other system on a car gives you a second chance. The restraint system fires once, in the few milliseconds that matter most, and every part in it is matched to a specific build. This is the area where ordering by description rather than by VIN stops being a commercial risk and becomes a safety one.
Diagnostics and repairBattery, alternator and starter by VIN: the charging system that has to be told what changed
Fitting a battery used to be the simplest job in the workshop. On a vehicle with stop-start and intelligent charging it is a parts decision, a chemistry decision and a coding procedure, and getting any of the three wrong shortens the life of the battery you just sold.
Parts sourcingSpotting counterfeit parts before they reach the vehicle
Counterfeit parts are not a problem of dodgy market stalls any more. They arrive in convincing boxes, through marketplaces that look legitimate, and the categories most often faked are the ones where failure hurts people: brakes, airbags, filters and steering components.
Workshop how-toAir conditioning parts by VIN: refrigerant type, compressor oil and the parts that will not mix
Air conditioning is the system where the wrong assumption is expensive twice: once for the part and once for the gas. Two refrigerants are in circulation, they need different equipment, and the compressor oil has to match the compressor rather than the shelf.
Diagnostics and repairSensors by VIN: why the one that looks identical is the wrong one
Sensors are the parts most often ordered on a description and most often returned. Two lambda sensors with the same thread and the same four wires can carry different cable lengths, different connectors and different calibration, and only one of them belongs on the car in front of you.
Diagnostics and repairTurbo parts by VIN: actuators, oil feeds and the failures that repeat
A turbocharger is one of the few parts that will destroy its replacement if the job around it is done carelessly. Actuator type, oil supply condition and the exact variant fitted to that build decide whether the repair lasts, and the differences rarely show in a photograph.
Workshop how-toTiming belt and chain parts by VIN: kits, revisions and single use bolts
Timing work is the job where being approximately right is the same as being wrong. Tensioners are revised during production, chain guides get updated after field failures, and half the fasteners around a timing cover are single use. All of it is tied to the build date behind the VIN.
Diagnostics & repairRacks, shafts and joints: steering and driveline parts without the guesswork
A driveshaft seems like honest, simple metal — until you learn one model can list a dozen of them. Length, spline count, joint sizes and intermediate bearings all follow the engine, the gearbox and sometimes the wheel size. Steering has the same character: one rack outline, several very different machines inside it.
Workshop how-toClutch and gearbox parts by VIN: dual mass, concentric slaves and expensive assumptions
A clutch quote given from the model name is a guess with four figures riding on it. The same car can carry a solid or a dual mass flywheel, a conventional release bearing or a concentric slave inside the bellhousing, and a gearbox whose code decides half the parts list.
Diagnostics & repairDPFs, catalysts and the emissions maze: identifying exhaust parts without expensive guesses
Nowhere on the car does a wrong guess cost more than under the floor. A diesel particulate filter can be four figures; catalysts are precious-metal pricing; and the same model wears different emissions hardware depending on market, standard and build month. This is the corner of the catalog where VIN-exact identification pays its whole annual salary in one order.
Workshop how-toCooling system parts by VIN: water pumps, thermostats and the repeat overheat
Cooling faults come back more often than most repairs, and the reason is usually a part that was close enough to fit and not close enough to work. Pump drive types, integrated thermostat housings and radiators specified around the gearbox all change within a model, and all of them are keyed to the build.
Workshop how-toAnatomy of a perfect parts lookup: one VIN, one brake job, every decision shown
Guides tell you the rules; this one shows the game. Below is a single, ordinary job — front brakes on a seven-year-old German hatchback — walked from phone call to order, with every decision narrated. Nothing here is exotic. That’s the point: the perfect lookup is boring, and boring is what keeps parts from coming back.
Parts dataSprings, dampers and the paint-dot lottery: suspension parts by VIN
Look closely at a coil spring and you’ll find dabs of coloured paint on the coils. That’s not decoration — it’s the factory telling you which of several near-identical springs this is. Suspension is the most variant-dense corner of the car, and the paint dots are your warning that “a spring for that model” is not an identification.
Diagnostics & repairThe right part isn’t always plug-and-play: coding, adaptation and married components
The part is genuine, VIN-matched, physically perfect — and the car still refuses to accept it. Welcome to the growing family of components that need a digital handshake after fitting: coding, adaptation, registration or outright marriage to the car. Identifying them in advance is the difference between a finished job and a stranded one.
Parts dataHot-climate radiators, cold-climate heaters: how geography edits the parts list
Carmakers do not build one car for the world. They build the Gulf version with the bigger radiator, the Nordic version with the fuel-fired heater, the dusty-market version with the extra filtration — all under one model name. Geography is an option package, and it splits parts exactly the way a sports pack does.
Workshop how-toFilters by VIN: the service parts that change mid-production without telling anyone
Filters are the cheapest parts on the invoice and the most common reason a service stalls halfway through. Housings change during a model run, cabin filters come in singles and pairs, and the fuel filter may not be a serviceable item at all. All of it is decided by the build behind the VIN.
Parts sourcingDonor-car parts: proving a used part fits before you drive to the breaker
Used parts are the best value in the business when they fit and the worst errand in the business when they don’t. The difference is provable before you travel: two VINs — donor and recipient — resolved in the official catalog, and one question asked: do they call for the same number?
How-toBefore you buy that used car, read its VIN like a parts catalog does
Everyone runs a history check before buying used. Almost nobody runs a build check — and the build is where the advert quietly stretches the truth. The VIN, read the way a parts catalog reads it, tells you what the car actually is: which options it was born with, which engine it really carries, and whether the “fully loaded” claim survives contact with the factory record.
Vehicle identificationWhen the VINs don’t match: a field guide to plates, stamps and stickers that disagree
A car carries its VIN in several places — etched at the windscreen, stickered on the door, stamped into the body, echoed in the electronics. They are supposed to agree. When they don’t, the car is telling you a story, and you want to hear it before you order parts against the wrong identity.
Vehicle identificationVIN myths that cost money: eight things people still believe at the parts desk
The VIN is the most useful seventeen characters on a car, and also the most mythologised. Some of the things everyone “knows” about it are true, some were true once, and some were never true — and the gaps between those categories are where money leaks. Score yourself against these eight.
Workshop how-toBrake parts by VIN: the variants that turn a routine job into a comeback
Brakes look like the safest parts order on the counter and generate some of the most returns. One model can carry three front disc diameters, two pad shapes and a choice of wear sensor, all decided by an option code the customer has never heard of. The VIN is what separates them.
Workshop economicsThe wrong-part case files: five real failures, decoded
Every parts desk has a drawer of stories it would rather forget. Here are five of them, reconstructed like incident reports: what was ordered, why it looked right, and the exact moment the lookup went wrong. None of these people were careless. All of them were one habit away from a clean job.
Collision and bodyFinding the paint code: why the VIN alone will not give you the colour
The VIN identifies the car. The paint code identifies the colour it left the factory in, and those are two different pieces of data. On most vehicles the code lives on a sticker or plate, and the catalog reaches it through the build record rather than by decoding the seventeen characters.
Workshop how-toUsing assembly diagrams to plan a repair before the spanners come out
Most people open an exploded diagram to find one number and close it again. Read the whole thing and it becomes a plan of the job — the order of disassembly, what has to come off first, and every fixing and seal you’ll need before you start.
Parts sourcingParts for imported and grey-market vehicles: when the local catalog doesn’t match
The car is a model you know well, but every number you try is subtly wrong. It is an import — built for another market — and the local catalog was never describing it. The fix is not more searching; it is looking in the right market’s data.
Vehicle identificationWhere to find the VIN on a vehicle, and which one to trust when they disagree
Start at the bottom of the windscreen on the driver’s side, then the driver’s door jamb. Those two cover most cars built since the mid-1980s. Everything after that is for the cars that make you work for it, and for the moment when two numbers on the same vehicle do not agree.
AftersalesWarranty and recall parts: identifying the updated number the campaign expects
A warranty or recall job is not the place to fit the number the car was born with. These repairs exist because a part was improved — and the whole point is to fit the updated component the campaign specifies. Identifying it correctly is half the job.
Workshop how-toWheels, tyres and TPMS by VIN: fitment, offsets and the sensor that gets forgotten
Wheels look like the simple end of the parts business, until a rim fouls a bigger brake, a sensor won’t pair, or the “same” car takes a different offset. The corner of the car with the most fitment traps rewards a VIN-exact lookup as much as any engine part.
EV & new techFinding EV parts in the EPC: high-voltage components, batteries and what’s different
EVs change the parts list more than the workflow. The catalog still turns a VIN into the exact components — but the components are new, the variants are finer, and getting the high-voltage parts right carries a weight that a wiper blade never did.
Parts dataVariant traps: why “it looks the same” is the most expensive phrase at the parts desk
Two cars on the forecourt look identical. Same shape, same badge, same year. One takes the part you ordered and one doesn’t. “It looks the same” is how the wrong part gets confidently sent.
Vehicle identificationModel year vs production date: the split that quietly breaks parts lookups
A customer says “it’s a 2019”. That single number hides three different dates, and parts change between them. Treat them as one and you’ll order a part for a car built six months either side of the one you’re holding.
AftersalesHow to verify a part fits before you order it
The cheapest place to catch a wrong part is the fifteen seconds before you click order. After that, catching it costs a return, a delay and a phone call.
Diagnostics & repairReading torque specs & assembly notes from the catalog
The part number tells you what to fit. The notes tell you how to fit it so it doesn’t come back. Skip them and a correct part still becomes a comeback.
Catalog dataFinding parts for classic & older vehicles in the EPC
Older vehicles are where catalog quality shows. The diagrams are still there, but the part numbers have moved through years of changes, and a lazy lookup hits dead ends a careful one walks straight past.
Workshop economicsMulti-brand workshops: managing many EPC catalogs without losing your mind
The independent that fixes everything pays a hidden tax: a different catalog, login and habit for every make through the door. That tax shows up as slow lookups, errors and staff who only “know” two of the brands.
Parts terminologyExchange parts, cores and deposits: what “reman” really means on the invoice
The invoice shows a deposit the customer didn’t expect, for a part they’re handing back. Exchange units are one of the most cost-effective ways to repair a car — once you understand the core, the charge and how the catalog lists them.
TrainingOnboarding a new parts advisor to EPC tools: a first-week guide
A new advisor can be quoting accurately by the end of week one — or picking up bad habits that cause returns for a year. The difference is what you teach first.
Parts dataHow parts kits work: bundles, repair kits and the loose-to-kit trap
Kits save time when you understand them and cost time when you don’t. The trap is ordering a loose part the manufacturer now sells only in a kit — or buying a whole kit when you needed one piece.
Catalog dataEPC vs aftermarket catalogs: when to use which (and why you need both)
EPC and aftermarket catalogues aren’t rivals — they’re two stages of one job. One tells you exactly what the car needs; the other helps you decide where to buy it. Use them in the wrong order and both let you down.
Parts counterCustomer-supplied parts: checking them against the catalog before they cost you
The customer arrives with a box from an online seller and a job booked in. Fit it, they say. The professional move is not to refuse and not to fit blind — it is to check that part against the official catalog for their VIN before it touches the car.
Parts sourcingCross-referencing OEM numbers to aftermarket — the right way round
Cross-referencing has a direction. Start from the right genuine number and you can pick any quality equivalent safely. Start from a guess and every cross-reference inherits the guess.
Parts sourcingOE supplier brands: matching Bosch, Valeo and the rest from the OEM number
A customer wants the quality without the dealer markup. Often the honest answer is the OE-supplier part — the very component the factory fits, in the supplier’s own box. The trick is matching it safely, and that always starts from the genuine OEM number.
Parts sourcingKeys, locks and the parts that guard the car: ordering security components by VIN
Most parts fit a build. Security parts fit one physical car: the key that turns this lock, the cylinder that matches that key, the remote the immobiliser will actually listen to. It is the corner of the catalog where the VIN stops being a convenience and becomes the whole mechanism — and where a legitimate order always travels with proof of ownership.
Workshop how-toFinding engine & gearbox parts by engine code: the detail that decides the part
Two cars, same badge, same year, and a water pump that fits one and not the other. The difference is under the bonnet: the engine code. Miss it and you order a perfectly good part for the wrong engine.
Workshop how-toClips, seals and fasteners: the small parts that cause the second trip
The caliper turned up on time. The job still stopped — because the guide-pin boots, the one-time-use bolts and the copper washer were not on the order. The big part is rarely what holds a repair up. The small hardware is.
Collision & bodyWindscreens, glass and lighting: the see-through parts with invisible variants
Glass looks like the simplest order on the sheet — it’s a windscreen, how many can there be? For one popular hatchback: eleven. Rain sensor or not, camera bracket or not, heated or not, acoustic laminate or not, head-up display or not. All the same shape. All different part numbers. Lighting plays the same trick with three technologies behind one lens outline.
Workshop how-toBuilding the correct service kit by VIN: filters, fluids and the specs that bite
A service looks like the safe, routine job — until the oil filter is a different housing on this engine variant, or the gearbox wants a specific fluid the generic listing never mentions. Building the kit from the VIN turns a routine job back into a routine job.
Fleet & logisticsEPC for fleets: one identification workflow across a mixed fleet
A mixed fleet is a parts problem disguised as a vehicle problem. Twelve makes, twelve ways to look up a part, and a downtime clock running on every one. Standardising identification is where fleet maintenance gets predictable.
Vehicle identificationFrom brass plates to seventeen characters: a short history of the VIN
The seventeen characters at the base of your windscreen are so ordinary that nobody looks at them twice. They are also one of the quiet triumphs of industrial standardisation — the reason a parts desk in Lisbon can identify a car built in Nagoya in under a minute. It took most of a century to get there.
Vehicle identificationThe data plate and option codes: reading the parts a VIN alone won’t show
A VIN tells the catalog which car you are holding. The data plate and its option codes tell you how that particular car was actually built — the paint, the trim level, the towing prep, the brake package. Miss them and you order the right part for the wrong specification.
Parts counterThe parts-desk checklist that cuts wrong-part returns
Returns don’t need a big system to fix. They need the same few checks, run every time, until they’re automatic. Here’s the short list that catches most of them.
Workshop economicsHow to quote a repair accurately with the EPC (and stop the quote from growing)
The quote that grows halfway through a job costs you twice: the awkward call to the customer and the trust you spend explaining it. A complete quote starts in the catalog, not in your head.
Diagnostics & repairElectrical & wiring parts: why VIN-exact identification matters most here
Nowhere does “close enough” fail faster than electrics. A connector with one extra pin, a module with the wrong coding, a harness for the car with the option yours doesn’t have. The VIN is the only thing that keeps electrical parts honest.
Collision & bodyFinding body & collision parts in the EPC: clips, fasteners and the build traps
Body work punishes a wrong part harder than anywhere else. A bumper that’s “almost right” doesn’t bolt up, the sensor holes don’t line up, and the customer’s car sits in the booth while you reorder. The catalog is how you get it right the first time.
Parts terminologyHow to read OEM part numbers by brand: VAG, BMW, Toyota, Mercedes and more
You don’t have to memorise every brand’s numbering scheme. Recognising the shape of a number tells you which group a part belongs to and flags a mistyped digit before it becomes a wrong order.
Parts sourcingDiscontinued and NLA parts: what to do when the number comes back dead
“No longer available” sends a job to a halt and a customer to a competitor. Before you accept it, the catalog often has an answer the parts line didn’t mention.
Workshop how-to10 VIN-lookup mistakes that send the wrong part out the door
Almost every wrong part traces back to the same short list of mistakes. None of them are exotic. Fix these ten habits and your return rate drops without you working any harder.
Vehicle identificationHow to decode a VIN for parts: WMI, VDS and VIS made useful
You don’t need to memorise the VIN standard to use it well. You need to know which characters carry which meaning, why one wrong digit ruins a lookup, and how the catalog turns those 17 characters into one exact car.
AftersalesBuilding a fast parts-lookup workflow that doesn’t cut corners
Speed and accuracy feel like a trade-off until you have a workflow. The same five moves, every time, and a part that used to take a careful five minutes takes a confident ninety seconds.
Parts terminologyOEM, OE, genuine, aftermarket: the parts terms cleared up for good
Four words get used as if they mean the same thing, and the confusion costs sales and trust. Pin down OEM, OE, genuine and aftermarket once, and your quotes get clearer and your customers stop arguing.
Parts counterEPC catalogs for the parts counter: a plain guide for parts advisors
A trade customer reads you a VIN over a noisy phone line and wants a price in thirty seconds. The EPC is how you give it without guessing — and without the return that costs you the next three calls.
Workshop how-toHow to read an exploded parts diagram (and stop ordering the wrong clip)
An exploded diagram looks like a parts explosion frozen mid-air. Once you know how to read one, it tells you everything: which part, how many, whether it comes loose or in a kit, and what bolts to it. Miss the small print and you order the clip that doesn’t exist.
Vehicle identificationVIN, chassis and frame numbers: what you’re really reading, and why it matters for parts
People use “VIN”, “chassis number” and “frame number” as if they’re interchangeable. Most of the time the distinction doesn’t matter — until you’re looking up parts on certain markets and makes, where using the wrong one quietly gives you the wrong car.
Parts dataPart supersessions: why the number printed on the box is often already wrong
You read the number straight off the old part. You order it. It arrives — and it’s subtly wrong, or it’s been replaced by something else entirely. The part wasn’t lying to you. It was just out of date, and the box never gets updated.
How-toHow to find the correct OEM part number by VIN — the professional workflow
There is a reliable, repeatable way to go from a 17-character VIN to the one genuine part number you need — the same way a franchised dealer does it. It takes about a minute once you know the steps, and it removes almost every common cause of a wrong part.
Workshop economicsThe real cost of a wrong part: how mis-identification drains a workshop’s time, money and reputation
Ask a workshop owner what a wrong part costs and they’ll quote you the price of the part. That’s the smallest number in the equation. The expensive part of a wrong part is everything that happens around it.
Catalog dataOfficial EPC catalogs vs third-party copies: why the source decides whether the part fits
Two catalogs can show the same exploded diagram and the same-looking part number — and only one of them will actually get the right component onto the van. The difference is almost never the picture. It is where the data came from.