Reference
Glossary
Plain definitions of the terms in owner's manuals, inspection reports, estimates and warranty booklets, as this manual uses them.
Each term as this manual uses it, with the chapter that explains it. Where a maker or an agency defines a term its own way, the chapter gives that definition and its source.
| Term | Meaning | Explained in |
|---|---|---|
| 12-volt battery | The small battery that starts a gasoline or diesel engine and powers lights and electronics. Hybrids and electric cars have one too. | Brakes, battery, wipers and lights |
| ABS (anti-lock braking system) | Keeps the wheels from locking in a hard stop. | Warning lights and codes |
| Administrator | The company that decides claims under a service contract. | Recalls, warranties and service contracts |
| Aftermarket part | A new part made by a company that did not make your car. | Reading a repair estimate |
| Alignment | The angles at which the wheels meet the road, set to the maker's specifications. | Tires |
| Alternator | The engine-driven generator that keeps the 12-volt battery charged; part of the charging system. | Brakes, battery, wipers and lights |
| API service symbol and ILSAC mark | The marks on an oil bottle that name the performance category the oil meets, from the American Petroleum Institute and the International Lubricant Standardization and Approval Committee. | Oil, fluids and filters |
| Arbitration | A neutral person hears both sides of a dispute and decides it. | Choosing a shop and handling problems |
| ASE certification | Tests for individual technicians from the National Institute for Automotive Service Excellence, with experience and retesting required. | Choosing a shop and handling problems |
| Authorization | Your permission for specific work at a specific price, best given in writing. | Reading a repair estimate |
| Automatic transmission fluid (ATF) | Lubricates and cools an automatic transmission and carries the pressure it shifts with. | Oil, fluids and filters |
| Balancing | Small weights added to a wheel so it spins without vibrating. | Tires |
| Basic warranty | The maker's broadest warranty (often called bumper to bumper), shorter than the powertrain warranty. | Recalls, warranties and service contracts |
| Book time, flat rate | A published labor time for a job, from a labor guide, charged whatever the job actually takes. | Reading a repair estimate |
| Brake fluid | The liquid that carries the pedal's force to the brakes. It absorbs moisture over time. | Oil, fluids and filters |
| Brake pad, caliper, rotor | On disc brakes, the caliper presses friction pads against the rotor, a disc that turns with the wheel. | Brakes, battery, wipers and lights |
| Buyers Guide | The window sticker the FTC's Used Car Rule requires on a dealer's used car. It says whether the car is sold as is or with a warranty. | Your service records |
| Cabin air filter | Cleans the air that comes into the car through the vents. | Oil, fluids and filters |
| Carbon monoxide | A poisonous gas in engine exhaust, with no smell or color. | Brakes, battery, wipers and lights |
| Catalytic converter | The exhaust part that cleans the exhaust gases. A misfire can damage it. | Warning lights and codes |
| Check engine light (MIL) | The malfunction indicator lamp: it lights when onboard diagnostics find a fault in the engine, emissions or powertrain system. | Warning lights and codes |
| Code (diagnostic trouble code) | A short code, such as P0300, naming the fault the onboard diagnostics detected. It points to a test, not to a part. | Warning lights and codes |
| Code reader | A device (scan tool) that reads codes from the car's diagnostic port. | Warning lights and codes |
| Comeback | A car returning with the same problem after a repair. | Choosing a shop and handling problems |
| Concern, cause, correction | The three parts of a repair order: what you noticed or asked for, what the technician found, and what was done. | Your service records |
| Coolant (antifreeze) | The fluid that carries heat from the engine to the radiator. | Oil, fluids and filters |
| Coolant reservoir | The translucent tank with two level marks where the coolant level is read, cold. | Oil, fluids and filters |
| Core, core charge | The old part that goes back to be rebuilt when a rebuilt or exchange part is installed, and the charge that may apply if you keep it. | Reading a repair estimate |
| Date code | The last four digits of a tire's DOT code: the week, then the year, it was made. | Tires |
| Declined, deferred | An item you said no to, or put off to a recheck point. | Discussing recommendations |
| Deductible | What you pay per visit under a service contract before it pays. | Recalls, warranties and service contracts |
| Diagnosis | The technician's testing that finds the cause of a problem, from the code through the test procedure. | Warning lights and codes |
| Diagnosis fee | The charge for that testing. Ask whether it applies to the repair. | Reading a repair estimate |
| Digital vehicle inspection (DVI) | Inspection results in shop software, with photos and colored marks, sent to your phone or email. The colors are each shop's convention. | Discussing recommendations |
| Discard thickness | The minimum thickness at which a brake rotor is replaced. | Brakes, battery, wipers and lights |
| DOT code (tire identification number) | The code molded on a tire's sidewall after the letters DOT. Its last four digits are the date code. | Tires |
| Electronic stability control (ESC) | Brakes individual wheels to help keep the car on its path. | Warning lights and codes |
| Emissions inspection (I/M) | A state or local check that plugs into the diagnostic port; a lit check engine light can fail it. | Warning lights and codes |
| Emissions warranty | The federal warranties on emission parts: 2 years or 24,000 miles, and 8 years or 80,000 miles for specified major components. | Recalls, warranties and service contracts |
| Engine air filter | Cleans the air the engine takes in. | Oil, fluids and filters |
| Estimate | The shop's statement, before work, of the proposed work and its expected cost. | Reading a repair estimate |
| Flush | In this manual, any service sold as a flush, exchange, cleaning, treatment or conditioning. | Oil, fluids and filters |
| GVWR (gross vehicle weight rating) | The most the vehicle may weigh fully loaded, as its maker rates it. | Hybrids and electric cars |
| High-voltage battery | The large battery that drives the motor in a hybrid or electric car. Only trained technicians service it. | Hybrids and electric cars |
| Hours per repair order | The labor hours billed on each visit's repair order, a figure service desks are measured on. | Discussing recommendations |
| Hybrid, plug-in hybrid, electric car | A hybrid has an engine and a motor with a battery it charges itself; a plug-in hybrid also charges from an outlet; an electric car has no engine. | Hybrids and electric cars |
| In-service date | The day the car was first delivered to its first buyer, or first used as a demonstrator or company car. Warranties count from it. | Hybrids and electric cars |
| Inverter | The power electronics between the high-voltage battery and the motor; some hybrids have their own inverter coolant. | Hybrids and electric cars |
| Labor guide | A database of average labor times per repair for each model. | Reading a repair estimate |
| Labor rate | The shop's price for one hour of labor. | Reading a repair estimate |
| Lemon law | A state remedy when the maker cannot fix a warranty defect after a reasonable number of tries. | Recalls, warranties and service contracts |
| Load index, speed rating | On a tire size, a number for the weight the tire is rated to carry and a letter for its rated top speed. | Tires |
| Maintenance schedule | The carmaker's list of services for one model and year, each with an interval in miles, months or both. | Your maintenance schedule |
| Maker specification (oil) | A carmaker's own oil standard, required on top of or instead of the API and ILSAC marks. | Oil, fluids and filters |
| Markup, margin | Markup is the gap between cost and price figured on cost; margin is the same gap figured on the selling price. | Reading a repair estimate |
| Mechanic's lien | A shop's legal claim on a car for unpaid charges, which in some states lets it keep the car until paid. | Choosing a shop and handling problems |
| Mediation | A neutral person helps both sides of a dispute agree. | Choosing a shop and handling problems |
| Misfire | A cylinder that is not firing as it should. A flashing check engine light can mean one. | Warning lights and codes |
| Multi-point inspection | A checklist inspection of the brakes, tires, fluids, belts, lights and other items the shop chooses. | Discussing recommendations |
| NMVTIS | The National Motor Vehicle Title Information System, the federal title database. It holds title, brand and odometer records, not repair history. | Your service records |
| Normal and severe schedules | The maker's default intervals, and the shorter intervals or extra items for driving the maker defines as harder on the car. | Your maintenance schedule |
| Not-to-exceed amount | The most the shop may charge without calling you first. | Reading a repair estimate |
| OEM part | A part made by or for the carmaker (original equipment manufacturer). | Reading a repair estimate |
| Oil life monitor | A system that estimates when the oil is due from how the car has been driven, shown as a percentage, message or code. It does not measure the oil level. | Your maintenance schedule |
| Onboard diagnostics (OBD) | The system that detects faults, stores codes and turns on the check engine light. | Warning lights and codes |
| Recall | A maker's campaign to fix a safety defect or a failure to meet a federal safety standard. | Recalls, warranties and service contracts |
| Recheck point | The mileage or date at which an item is measured or decided again. | Discussing recommendations |
| Regenerative braking | The motor slows the car as a generator and returns energy to the battery, which reduces brake wear. | Hybrids and electric cars |
| Remanufactured, rebuilt | A used part restored for reuse; the FTC says the words generally mean the same thing. | Reading a repair estimate |
| Remedy | The repair, replacement or refund a maker offers for a recall. | Recalls, warranties and service contracts |
| Repair order, invoice | The shop's record of your concern and the work you authorized, and, when finished, of what was done and charged. | Reading a repair estimate |
| Repair warranty | The shop's own promise on its parts and labor. There is no standard one. | Choosing a shop and handling problems |
| Rotation | Moving each tire to another position, in the maker's pattern, so wear evens out. | Tires |
| Serpentine belt | The belt that drives the engine's accessories, such as the alternator. | Sounds, smells, leaks and feel |
| Service advisor | The person at the service desk who writes up your concern, presents findings and estimates, and takes your approval. | Discussing recommendations |
| Service contract | A contract, bought separately, to pay for maintenance or repairs over a set period. Under federal law it is not a warranty. | Recalls, warranties and service contracts |
| Shop supplies | Small materials used on a job. Some states limit how they are charged. | Reading a repair estimate |
| Spark plugs | Ignite the fuel in each cylinder of a gasoline engine; a schedule item at a set mileage. | Oil, fluids and filters |
| Specified major emission control components | The parts with the 8-year or 80,000-mile emissions warranty, listed in 40 CFR 85.2103. | Recalls, warranties and service contracts |
| Storage charges | Daily charges while a shop holds a car. | Choosing a shop and handling problems |
| Tear-down | Taking part of the car apart to find a fault, estimated and charged separately. | Reading a repair estimate |
| Technical service bulletin (TSB) | Maker-to-dealer guidance on a recurring problem and its repair. Usually a paid repair unless a warranty covers it. | Recalls, warranties and service contracts |
| Telltale | The federal term for a warning light. | Warning lights and codes |
| Timing belt | A toothed belt inside some engines that keeps the engine's parts turning in step; many engines use a chain instead. | Oil, fluids and filters |
| Tire placard | The Tire and Loading Information label on the driver's door edge or post, which gives the cold pressures. | Tires |
| Tire pressure, cold | Pressure read before the car has been driven, or after it has sat at least three hours. | Tires |
| Title brand | A label a state records on a car's title, such as salvage or flood. | Your service records |
| TPMS (tire pressure monitoring system) | The system that lights a yellow warning when a tire is well below its placard pressure. It is not a substitute for a gauge. | Tires |
| Tread depth, wear bar | Groove depth in 32nds of an inch, and the raised bar across the grooves at 2/32 in. | Tires |
| VIN | The 17-character vehicle identification number, used for schedules, recalls and history reports. | Your maintenance schedule |
| Viscosity grade | A code such as 0W-20 or 5W-30, under SAE J300, that rates how the oil flows. | Oil, fluids and filters |
| Warranty extension (adjustment program) | Coverage of a known problem beyond the warranty, without a recall; sometimes called a secret warranty. | Recalls, warranties and service contracts |
| Wear indicator | A metal tab on a brake pad that squeals against the rotor as the pad wears thin. | Brakes, battery, wipers and lights |
| Work order | The form the job is written on before work starts; sign it only when it is filled in. | Sounds, smells, leaks and feel |
Terms on estimates and invoices, with their sources and the state examples, are on Estimate terms.