Ever looked at a service report and thought, “What on earth is an inner CV boot?” You’re not alone. Mechanics have a language all of their own, and this glossary translates it into plain English. Whether it’s a line on your quote, something on your invoice or a word your mechanic used at the counter, you’ll find it here. Jump to a section, use the A–Z index, or start with the terms people ask about most. And because cars keep changing, so does this list. We add new terms all the time.
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Most-Asked Terms
- Logbook service · Blue slip · Pink slip · CV joint · CV boots
- Engine mounts · Timing belt · Brake rotors · Check engine light · Catalytic converter
A–Z Index
# · A · B · C · D · E · F · G · H · I · J · L · M · O · P · Q · R · S · T · V · W
A ABS (anti-lock braking system) · ABS light · Air filter · Airbag light · Alternator
B Backfire · Ball joints · Battery / charging light · Battery terminals & corrosion · Blue slip (NSW) · Brake calipers · Brake fade · Brake fluid · Brake hoses · Brake pads · Brake rotors (brake discs) · Brake warning light · Bushes (control arm bushes)
C Cabin (pollen) filter · Capped price servicing · Car battery · Catalytic converter · CCA (cold cranking amps) · Check engine light · Check engine warning light · Clutch · Coolant · CV boots (inner & outer) · CV joint (constant velocity joint) · CV shaft (drive shaft) · CVT (continuously variable transmission)
D Differential & diff oil · DPF (diesel particulate filter) · Drive belt (serpentine belt) · Dual-clutch transmission (DCT)
E EGR valve · Engine mounts · Engine oil & viscosity · Engine temperature light · Exhaust manifold
F Fixed price servicing · Flex pipe · Flywheel · Fuel filter · Fuses
G Genuine vs OEM-equivalent parts · Globes
H Handbook service (scheduled service) · Head gasket
I Idler & tensioner pulleys · Ignition coil
M Machining rotors (resurfacing) · Major service (Extensive Service) · Manual vs automatic transmission · Manufacturer’s warranty (new car warranty) · Minor service (Essential Service) · Misfire · Muffler
O OBD diagnostic scan · Oil filter · Oil pressure light · Oil seepage vs oil leak · Overheating · Oxygen (O2) sensor
P Park brake (handbrake) · Pink slip (NSW eSafety check) · Power steering
R Radiator · Radiator & heater hoses · Radiator flush (coolant flush) · Rear main seal · Roadworthy certificate (RWC – VIC) · Rocker cover gasket (valve cover gasket)
S Safety certificate (QLD) · Service interval · Service light reset · Service report · Shock absorbers · Spark plugs · Starter motor · Statutory warranty · Steering rack boots · Struts · Sump plug & sump gasket · Sway bar links · Synthetic oil
T Thermostat · Tie rod ends · Timing belt · Timing chain · TPMS (tyre pressure monitoring system) · Transfer case · Transmission fluid · Tread depth · Turbocharger · Tyre pressure (TPMS) light · Tyre rotation
W Water pump · Wheel alignment · Wheel balancing · Wheel bearings · Wiper blades
How to Read Your Service Report
Service reports use shorthand for where a part is, what condition it’s in and how urgent it is. Once you know the code, they’re a lot less scary. Here’s how to crack it.
Where on the Car
- LH / RH: left-hand and right-hand, as you sit in the driver’s seat. In Australia, LH is the passenger side and RH is the driver’s side.
- F / R: front and rear. Often combined, like LHF (left-hand front) or RHR (right-hand rear).
- Inner / outer: which end of a part it is. Inner is the end closer to the middle of the car, and outer is the end closer to the wheel. For example, each front wheel has a drive shaft with a rubber boot at both ends, so the report says whether it’s the inner or outer one.
- Upper / lower: which of two matching parts it is when one sits above the other. Some cars have two suspension arms holding each wheel, one on top of the other, so the report might say “lower arm bush” to show which one.
Condition Words
- Soft: a rubber mount or bush has lost its firmness and no longer holds the part steady.
- Worn: the part has worn down through normal use and is near the end of its life.
- Perished: rubber has dried out, hardened or cracked with age.
- Cracked: there’s a visible crack, usually in a hose, boot, belt or plastic part.
- Split / torn: the crack has gone all the way through, so the part isn’t sealing or protecting anymore.
- Seeping / weeping: a thin film of fluid around a seal or gasket, but nothing dripping yet.
- Leaking: fluid is actually dripping or running.
- Excessive play: a part wobbles or moves more than it should. A common sign of wear in steering and suspension.
- Noisy: it’s making a sound it shouldn’t (and your mechanic heard it too).
- At limit / below minimum: the part has worn to, or past, the manufacturer’s minimum, like brake pad thickness or tyre tread depth.
- Contaminated: a fluid has something in it that shouldn’t be there, like water in brake fluid or oil in coolant.
Seeping vs leaking: seeping or weeping means a slow film of fluid, usually one to keep an eye on. Leaking means fluid is dripping, and it usually needs fixing.
Common Invoice Line Items
Some lines turn up on invoices again and again, often in pairs. Here’s what they mean.
- Replace engine oil & filter: an oil change. The oil filter is almost always replaced at the same time, so fresh oil doesn’t run through an old, dirty filter.
- Rear brake pads / rear brake rotors: new brake pads at the back. Rotors are often replaced or machined at the same time, so the new pads sit on a flat, even surface.
- Machine front rotors: the front rotors have been resurfaced to make them smooth and flat again, rather than replaced.
- Replace air filter: a new engine air filter, so your engine breathes clean air.
- Wheel alignment: your wheel angles have been adjusted back to the manufacturer’s settings.
- R&R: remove and replace. The old part comes out and a new one goes in.
Other Abbreviations You Might See
- ATF: automatic transmission fluid. It’s the oil that keeps an automatic gearbox lubricated, cool and shifting smoothly. If it’s low or old you might notice rough, delayed or slipping gear changes. Read more about transmission fluid.
- PAS: power-assisted steering, or power steering for short. It’s the system that makes your steering wheel easy to turn, especially at low speeds like parking.
- A/C: air conditioning.
- DTC: diagnostic trouble code. The fault code stored by your car’s computer, read with a diagnostic scan.
- OEM: original equipment manufacturer. Parts made to the same spec as the ones your car left the factory with.
- RWC: roadworthy certificate.
How Urgent Is It?
Most reports sort items by priority. The wording varies between workshops, but it usually looks something like this:
- Safety item / urgent: get it fixed before you drive much further. It affects how your car brakes, steers or holds the road.
- Recommended: it needs doing soon, but it isn’t dangerous today. Worth planning for.
- Monitor / check at next service: we’ve spotted early wear. Nothing to do yet, but we’ll keep an eye on it.
Whatever’s on your report, we’ll explain each item, what’s urgent and what can wait. At Midas, we make sure nothing gets done without your OK.
Decoding a real service report – Example:
“LH front CV shaft – inner boot leak”: on the front passenger-side drive shaft, the rubber boot at the gearbox end has split and grease is escaping. Left alone, dirt and water get into the CV joint and wear it out, which costs more than replacing the boot or shaft early.
“Engine mounts soft”: the rubber mounts holding your engine in place have lost their firmness. You might feel more vibration, or a clunk when you take off. Left too long, the engine moves more than it should and puts strain on nearby hoses and parts.
“Air filter dirty – replace”: your engine air filter is clogged. A new one lets your engine breathe properly and helps keep fuel use in check.
Car Servicing & Paperwork Terms
The admin side of owning a car. Not the most exciting bit, but knowing these terms makes life at the service counter a whole lot easier.
Logbook service
A logbook service is a car service done to your manufacturer’s schedule, with your logbook stamped at the end. It’s how you keep your new car warranty’s servicing conditions met, and no, it doesn’t have to be done at the dealer. Read more: logbook service.
Handbook service (scheduled service)
A handbook service is another name for a logbook service, done to the schedule in your car’s handbook. Same thing, different name.
Minor service (Essential Service)
A minor service is a basic service covering an oil and filter change, fluid top-ups and a safety inspection. At Midas, that’s our Essential Service. Think of it as a regular check-up for a car that’s in good nick.
Major service (Extensive Service)
A major service is a more comprehensive service that checks and replaces more parts than a minor service. At Midas, that’s our Extensive Service, a smart call if your car’s overdue or racking up the kilometres.
Service interval
A service interval is the time or distance between services, set by your manufacturer, like every 12 months or a set number of kilometres, whichever comes first. Think of it as your car’s appointment calendar. Your logbook lists yours.
Service light reset
A service light reset turns off the “service due” reminder on your dashboard after a service, so it can count down to the next one. If it pops back on, you’re due again (not haunted).
Capped price servicing
Capped price servicing is a carmaker’s program that sets the maximum price of scheduled dealer services, usually for a set number of years or kilometres. Handy, but the cap only covers the scheduled items, so any extra repairs are charged on top.
Fixed price servicing
Fixed price servicing means you know the price of a defined service upfront, before any work starts. No nasty surprises when you pick up your keys. Anything extra we find gets quoted separately.
Statutory warranty
Statutory warranty usually refers to your rights under Australian Consumer Law, known as consumer guarantees. They apply automatically, on top of any manufacturer’s warranty, and last for a reasonable time depending on the product and price paid.
Manufacturer’s warranty (new car warranty)
A manufacturer’s warranty is the carmaker’s promise to fix certain faults for a set period or distance. Under ACCC guidance, servicing at an independent workshop like Midas won’t void it, as long as it’s done to manufacturer specification by qualified mechanics using quality parts. Read more: 5 things to know about car warranties.
Genuine vs OEM-equivalent parts
Genuine parts are made or branded by your carmaker. OEM-equivalent parts are made to the same specifications and quality, often by the same suppliers. Both meet your warranty’s servicing conditions when they’re of appropriate quality and fitted properly. OEM means Original Equipment Manufacturer.
Quote vs estimate
A quote is a set price for a defined job. An estimate is a best guess that could change once the work starts. At Midas, you get a quote before we pick up a spanner.
Service report
A service report is the summary your mechanic gives you after a service or inspection, listing what was checked, what was done and anything that needs attention. Not sure what yours says? That’s what this glossary is for. Start with how to read your service report.
Vehicle safety check
A vehicle safety check is a quick inspection of the parts that keep you safe, like brakes, tyres, lights and wipers. Perfect before a long road trip, or when something just feels a bit off. See our 5-Point Safety Check.
Roadworthy certificate (RWC – VIC)
A roadworthy certificate (RWC) is a certificate from a licensed vehicle tester confirming a car is safe enough for the road. In Victoria, you generally need one to sell a registered car or to re-register one. It checks safety items only, not the car’s overall condition. Transport Victoria: Roadworthy certificate
Safety certificate (QLD)
A safety certificate is Queensland’s version of a roadworthy. You need one to sell a registered light vehicle in QLD, and it’s issued by an approved inspection station. Queensland Government safety certificate
Blue slip (NSW)
A blue slip is a detailed NSW inspection, done at an Authorised Unregistered Vehicle Inspection Station, for cars that are unregistered, have been off the road for a while, or were written off and repaired. It’s more thorough than a pink slip. Service NSW blue slip
Pink slip (NSW eSafety check)
A pink slip (or eSafety check) is the yearly NSW safety inspection needed to renew registration on most light vehicles over five years old. It covers the basics, like brakes, tyres, lights and steering. Service NSW pink slip
Engine Terms
The engine bay is where most of the jargon lives. Here’s what it all means, without the grease under your fingernails.
Engine oil & viscosity
Engine oil is the lifeblood of your engine, keeping all the moving parts inside it slippery and cool. Viscosity is how thick it is, shown as a code like 5W-30: the first number is how it flows when cold, the second when it’s hot. Your logbook says which one your car needs. Read more: different engine oils.
Synthetic oil
Synthetic oil is a man-made engine oil that holds up better at high temperatures and lasts longer than conventional oil. It’s the premium stuff, built to go the distance. Many newer cars need it, so check your logbook before topping up.
Oil filter
An oil filter traps dirt and metal particles in your engine oil. It’s usually replaced at every oil change, because there’s not much point putting fresh oil through a dirty filter. Here’s how to check your oil level.
Air filter
An air filter stops dust and dirt getting into your engine. Think of it as your engine’s face mask. A clogged one makes your engine work harder, which is why it’s such a common line on service reports. Read more: is it time to change your car filters?
Cabin (pollen) filter
A cabin filter cleans the air coming into the car through your vents. If your air con smells a bit funky or the airflow is weak, this is often the culprit.
Fuel filter
A fuel filter catches dirt and debris before fuel reaches your engine. Not every car has one that needs regular replacing, so your logbook will tell you if yours does.
Engine mounts
Engine mounts are rubber-and-metal brackets that hold your engine in place and soak up its vibration. When a report says “engine mounts soft”, the rubber has worn. You might feel more shaking when you’re stopped, or a clunk when you take off.
Rocker cover gasket (valve cover gasket)
A rocker cover gasket is the seal between the top of your engine and its cover. As it ages, it can seep oil, often noticed as a burning oil smell after a drive. Not a great air freshener.
Sump plug & sump gasket
The sump is the oil reservoir at the bottom of your engine. The sump plug is the bolt removed to drain old oil, and the sump gasket seals the sump to the engine. Either one can cause a slow drip on your driveway.
Rear main seal
A rear main seal is the seal at the back of the engine, where it meets the gearbox. It’s a small part but a big job, because the gearbox usually has to come out to reach it.
Oil seepage vs oil leak
Oil seepage is a light film of oil around a seal or gasket, usually something to monitor. An oil leak means oil is actually dripping, and it should be fixed before it turns into a bigger (and messier) problem. Read more: how to handle an oil leak.
Idler & tensioner pulleys
Idler and tensioner pulleys are small wheels that guide your engine’s drive belt and keep it tight. A worn one often makes a squealing or chirping noise, a bit like a bird has moved into your engine bay.
Spark plugs
Spark plugs create the spark that ignites the fuel in a petrol engine. Small part, big job. Worn plugs can cause rough running, hard starting and poor fuel economy, so they’re replaced at set intervals in your logbook.
Ignition coil
An ignition coil boosts your battery’s power into the much stronger charge your spark plugs need to make a spark. A failing coil is a common cause of misfires and a flashing check engine light.
Timing belt
A timing belt is a toothed rubber belt inside your engine that keeps its moving parts in perfect time, so everything opens and closes at exactly the right moment. It’s replaced at set intervals, because if it snaps, it can cause serious (and seriously expensive) engine damage. On some cars this means the car cannot be driven and could require towing. Read more: signs your engine belt needs repair.
Timing chain
A timing chain does the same job as a timing belt, but it’s a metal chain inside the engine. It’s built to last much longer, but not forever: it can stretch or start to rattle with age.
Drive belt (serpentine belt)
A drive belt (or serpentine belt) runs your car’s accessories, like the alternator, power steering and air con. A squeal on start-up is a classic sign it’s worn. This is not to be confused with a Timing Belt.
Head gasket
A head gasket is the seal between the top section of your engine and the main body underneath it. A blown head gasket can mix oil and coolant, cause overheating or white exhaust smoke. It’s a big repair, so it pays to catch the early signs.
Misfire
A misfire is when fuel doesn’t burn properly in one part of your engine. You’ll feel it as shaking, rough running or a loss of power, and it often sets off the check engine light.
Backfire
A backfire is a bang from the exhaust or intake caused by fuel burning in the wrong place, outside the engine. Read more: what causes a backfire in your exhaust.
Turbocharger
A turbocharger uses exhaust gas to force more air into the engine, giving more power from a smaller engine. Turbos love clean oil, so stick to your service schedule.
Check engine light
The check engine light is a dashboard warning that your car’s computer has found a fault with the engine or emissions system. Read more: why you shouldn’t ignore your check engine light.
OBD diagnostic scan
An OBD (on-board diagnostics) scan reads the fault codes stored in your car’s computer to pinpoint what’s wrong. Think of it as your car telling us where it hurts. It’s where diagnosis starts, so there’s no guesswork. See our vehicle diagnostics.
Cooling System Terms
Your engine makes a lot of heat. These are the parts that make sure it doesn’t hang on to it.
Coolant
Coolant is the fluid that carries heat away from your engine and stops it freezing or boiling. Low or old coolant is one of the most common causes of overheating. Read more: everything you need to know about your car’s coolant.
Radiator
A radiator cools hot coolant using the air flowing through it as you drive. Leaks, blockages or damage stop it doing its job. See our cooling system services.
Radiator & heater hoses
Radiator and heater hoses are rubber hoses that carry coolant between the engine, radiator and heater. They harden and crack with age, which is why “perished hose” shows up on so many reports.
Thermostat
A thermostat is a valve that opens and closes to control how much coolant flows, so your engine warms up quickly and stays at the right temperature. A stuck thermostat can cause overheating, or a heater that only blows cold. Not ideal on a winter morning.
Water pump
A water pump pushes coolant around your engine. When it fails, it often leaks or whines, and overheating usually isn’t far behind.
Overheating
Overheating is when your engine runs hotter than it should, shown by a rising temperature gauge or a warning light. Pull over when it’s safe, and never open the radiator cap while it’s hot. Read more: what to do if your car overheats.
Radiator flush (coolant flush)
A radiator flush drains the old coolant, cleans out the system and refills it with fresh coolant. Coolant loses its protection over time, so it’s out with the old and in with the new at set intervals.
Brake Terms
Arguably the most important parts on your car. Here’s what your mechanic means when they talk brakes.
Brake pads
Brake pads are the friction material that presses against your rotors to slow the car down. They wear down a little with every stop, so they’re one of the most common things we replace. See our brake services.
Brake rotors (brake discs)
Brake rotors are the metal discs your brake pads squeeze to stop the wheels. They wear too, and can warp, which you’ll feel as a shudder through the brake pedal or steering wheel.
Pads vs rotors: pads are the part that wears out first; rotors are what the pads grip. New pads on worn rotors won’t stop as well, which is why they’re often done together.
Machining rotors (resurfacing)
Machining rotors or discs means shaving a thin layer off to make them flat and smooth again, like giving them a fresh surface. It only works if there’s enough metal left. If not, they’re replaced. There are minimum measurements to stick to, so not all worn rotors can be machined.
Brake calipers
Brake calipers hold your brake pads and squeeze them against the rotors when you press the pedal. A sticking caliper can make your car pull to one side, wear brake pads unevenly or leave one wheel running hot.
Brake hoses
Brake hoses are flexible lines that carry brake fluid to each wheel. Cracked or perished brake hoses are a safety item, so they’re not one to put off.
Brake fluid
Brake fluid carries the force from your foot on the pedal to the brakes at each wheel. It absorbs water over time, which makes braking less effective, so it’s replaced at set intervals. Read more: why it’s essential to maintain your brake fluid level.
ABS (anti-lock braking system)
ABS stops your wheels locking up under hard braking, so you can still steer. Read more: the difference between ABS and traditional brakes.
Park brake (handbrake)
The park brake holds your car still when it’s parked. If you need to really haul on it, or the car still creeps, it probably needs adjusting. Electric handbrakes in many late model vehicles may need special attention or adjustment.
Brake fade
Brake fade is when your brakes become less effective because they’ve overheated, like on a long downhill drive. If your brakes feel weak in everyday driving, get them checked. Read more: signs your brakes need repair.
Steering, Suspension & Tyre Terms
The parts that keep your ride smooth, your steering sharp and your rubber on the road.
Shock absorbers
#shock-absorbers
Shock absorbers control how your car’s springs move, keeping your tyres on the road over bumps. Read more: the dangers of driving with worn shock absorbers and when to replace them.
Struts
#struts
A strut is a shock absorber and spring combined into one unit that also supports the weight of the car. Most modern cars have struts at the front. See our steering and suspension services.
Bushes (control arm bushes)
#bushes
Bushes are rubber cushions where suspension parts join, soaking up vibration and noise. You’ll often see “control arm bushes” on reports: these sit where the metal arms that hold each wheel attach to the car. Worn or soft bushes can cause clunks, vague steering and uneven tyre wear.
Ball joints
#ball-joints
Ball joints are pivot points that let your wheels move up and down and steer at the same time. Worn ball joints can clunk over bumps, and they’re a safety item, so don’t ignore them.
Sway bar links
#sway-bar-links
Sway bar links are short rods connecting the sway bar (a metal bar that stops your car leaning in corners) to the suspension. Worn links usually rattle or knock over bumps.
Wheel bearings
#wheel-bearings
Wheel bearings let your wheels spin smoothly. A worn one makes a humming or grinding noise that gets louder the faster you go. If your car suddenly sounds like a plane taking off, that could be why.
Tie rod ends
#tie-rod-ends
Tie rod ends connect your steering to your front wheels. When they’re worn, your steering can feel loose or wander, and your tyres can wear unevenly.
Steering rack boots
#steering-rack-boots
Steering rack boots are rubber covers that protect your steering rack, the part that turns your front wheels when you turn the steering wheel. A split boot is a much easier fix now than a worn-out steering rack later.
Power steering
#power-steering
Power steering makes your steering lighter. Older systems use power steering fluid (hello, “PAS” on your report), while many newer cars use electric power steering instead.
Wheel alignment
#wheel-alignment
A wheel alignment adjusts the angles of your wheels back to the manufacturer’s settings, so your car tracks straight. Read more: wheel alignment vs wheel balancing.
Wheel balancing
#wheel-balancing
Wheel balancing adds small weights to your wheels so they spin evenly. Unbalanced wheels cause vibration. If your steering wheel starts to shimmy on the highway, this is a likely cause.
Tyre rotation
#tyre-rotation
Tyre rotation means swapping your tyres between positions on the car, so they wear evenly and last longer. More kilometres from the same set of tyres? Yes please. See our tyre services.
Tread depth
#tread-depth
Tread depth is how much grip is left on your tyres. The legal minimum in Australia is 1.5 mm, but grip drops well before that, especially in the wet. Read more: how to tell when your tyres need replacing.
TPMS (tyre pressure monitoring system)
#tpms
TPMS watches your tyre pressures and warns you on the dash if one is low. When it lights up, check your pressures and have a look for a nail or damage.
Transmission & Drivetrain Terms
Everything that gets the power from your engine to your wheels.
Clutch
#clutch
A clutch connects and disconnects the engine from the gearbox in a manual car, so you can change gears. A slipping clutch (the revs rise but the car doesn’t speed up) means it’s wearing out. See our clutch and transmission services.
Flywheel
#flywheel
A flywheel is a heavy metal disc between the engine and the gearbox that the clutch presses against. It’s often checked, machined or replaced along with a new clutch.
Manual vs automatic transmission
#manual-vs-automatic
A manual transmission has a clutch pedal and a gear stick you shift yourself. An automatic changes gears for you. Read more: signs your automatic transmission needs repair.
CVT (continuously variable transmission)
#cvt
A CVT is a type of automatic with no fixed gears, so it feels smooth with no gear changes. CVTs can be a bit fussy about their fluid, so stick to the service schedule.
Dual-clutch transmission (DCT)
#dual-clutch
A dual-clutch transmission is an automatic that uses two clutches for faster gear changes. Some can feel jerky at low speeds when they need attention.
Transmission fluid
#transmission-fluid
Transmission fluid lubricates and cools your gearbox. In automatics, it’s called ATF. Old or low fluid can cause rough or slipping gear changes.
CV shaft (drive shaft)
#cv-shaft
A CV shaft (or drive shaft) is the metal shaft that carries power from the gearbox to your wheels. Front-wheel-drive cars have one on each side at the front.
CV joint (constant velocity joint)
#cv-joint
A CV joint is a flexible joint at each end of the CV shaft that lets your wheels keep turning while they steer and move up and down over bumps. A clicking noise when you turn sharply, like in a car park, is a classic sign it’s worn.
CV boots (inner & outer)
#cv-boots
CV boots are rubber covers that keep grease in and dirt out of your CV joints. The inner boot sits at the gearbox end and the outer boot at the wheel end. A split or leaking boot is worth fixing early, before it takes the CV joint with it.
Differential & diff oil
#differential
A differential (or diff) lets your left and right wheels turn at different speeds when you go around a corner (the outside wheel has further to travel). Diff oil keeps it lubricated and is changed at set intervals, especially on 4WDs.
Transfer case
#transfer-case
A transfer case sends the engine’s power to both the front and rear wheels on 4WDs and some AWDs. It has its own oil, which is checked and changed as part of your service schedule. See our 4WD servicing.
4WD vs AWD
4WD (four-wheel drive) lets you switch on drive to all four wheels for off-road grip, usually with a low-range setting for steep or slippery tracks. AWD (all-wheel drive) sends power to all four wheels automatically for better grip on the road.
Exhaust & Emissions Terms
What goes in must come out. These parts handle the fumes (and keep the noise down).
Muffler
#muffler
A muffler reduces the noise from your exhaust, so your car purrs instead of roars. Read more: muffler vs exhaust: what’s the difference?
Exhaust manifold
#exhaust-manifold
An exhaust manifold collects the exhaust gases coming out of your engine and sends them into the exhaust pipe. A cracked manifold often makes a ticking noise on cold starts. See our exhaust services.
Catalytic converter
#catalytic-converter
A catalytic converter turns harmful exhaust gases into less harmful ones before they leave your car. A failing one can trigger the check engine light, cause a rotten-egg smell (yep, really) or sap your power.
DPF (diesel particulate filter)
#dpf
A DPF traps soot from a diesel engine’s exhaust. It cleans itself by burning the soot off on longer drives, so diesels that only do short trips can block it up. Read more: read this before you choose to drive diesel.
EGR valve
#egr-valve
An EGR (exhaust gas recirculation) valve sends a small amount of exhaust gas back into the engine to reduce emissions. When it clogs up with carbon, it can cause rough idling and a check engine light.
Oxygen (O2) sensor
#oxygen-sensor
An oxygen sensor measures how much oxygen is in your exhaust, so the engine can get the right mix of fuel and air. A faulty one can push up your fuel use and trigger the check engine light.
Flex pipe
#flex-pipe
A flex pipe is a flexible section of the exhaust that absorbs the engine’s movement. When it cracks, your exhaust gets louder, often with a rattle or blowing sound. Your neighbours will notice. Read more: 5 quick checks to keep your exhaust healthy.
Battery & Electrical Terms
No spark, no start. Here’s the electrical stuff that keeps your car going.
Car battery
#car-battery
A car battery powers your starter motor and electronics when the engine’s off. Heat is its biggest enemy, which makes Aussie summers tough going. See car battery testing and replacement.
CCA (cold cranking amps)
#cca
CCA measures how much power a battery can deliver to start your engine in the cold. In other words, how well it copes on a chilly morning. A replacement battery should meet your car’s requirement.
Battery terminals & corrosion
#battery-terminals
Battery terminals are the connection points on top of your battery. White or green crusty build-up (corrosion) can stop your car starting, even with a healthy battery.
Alternator
#alternator
An alternator recharges your battery and powers the electrics while the engine’s running. A battery warning light while you’re driving often points to the alternator. See our mechanical repairs.
Starter motor
#starter-motor
A starter motor gets your engine spinning when you turn the key or press start. A single click and no start is a common sign it’s on the way out.
Fuses
#fuses
Fuses protect your car’s electrical circuits from damage. If something electrical suddenly stops working, a blown fuse is the first suspect.
Globes
#globes
Globes are the bulbs in your headlights, park lights, brake lights and indicators. A blown globe is a quick fix, and an important one, because other drivers need to see you.
Wiper blades
#wiper-blades
Wiper blades clear water from your windscreen. If they smear, streak or squeak their way across the glass, the rubber’s worn and it’s time for a new set.
Jump start
#jump-start
A jump start uses another battery (or a jump pack) to start a car with a flat battery. Needed one more than once? Get your battery and charging system tested.
Dashboard Warning Lights
Warning lights are your car’s way of tapping you on the shoulder. Some are a gentle nudge, others mean pull over now. Here’s what the common ones mean and how quickly to act. Symbols vary between makes, so check your owner’s manual too.
Check engine warning light
#check-engine-warning
The check engine light means your car’s computer has found an engine or emissions fault. If it’s steady, book a check soon. If it’s flashing, that often means a serious misfire, so pull over when it’s safe. Urgency: book soon (steady) / stop (flashing).
Oil pressure light
#oil-pressure-light
The oil pressure light (usually an oil can symbol) means your engine has lost oil pressure. This is one to take seriously. Stop as soon as it’s safe and switch the engine off, because driving on can wreck it. Urgency: stop now.
Battery / charging light
#battery-light
The battery light means your battery isn’t being charged, usually because of an alternator or drive belt problem. You’ve got limited time before the car stops. Urgency: get it checked straight away.
Engine temperature light
#temperature-light
The engine temperature light (usually a thermometer symbol) means your engine is overheating. Pull over when it’s safe, switch off and let it cool. Urgency: stop now.
Brake warning light
#brake-warning-light
The brake warning light means your park brake is on, your brake fluid is low or there’s a brake system fault. If the park brake is off and the light stays on, get it checked before you drive on. Urgency: stop and check.
ABS light
#abs-light
The ABS light means there’s a fault with your anti-lock brakes. Your normal brakes still work, but ABS may not kick in during hard braking. Urgency: book soon.
Tyre pressure (TPMS) light
#tpms-light
The tyre pressure light means one or more tyres is low. Check your pressures and look for damage. Urgency: check soon.
Airbag light
#airbag-light
The airbag light means there’s a fault in the airbag system, so your airbags may not work in a crash. Urgency: book soon. Read more: servicing your car’s airbag.
Still Not Sure What Your Car Needs?
Ask your local Midas mechanic. We’ll explain it before we do any work. Book online or find your nearest Midas store.
Glossary FAQs:
Both are NSW inspections. A pink slip is the yearly safety check for registration renewal on most cars over five years old. A blue slip is a more detailed inspection for cars that are unregistered, have been off the road for a while, or were written off and repaired.
Soft means a rubber part, like an engine mount or suspension bush, has lost its firmness and isn’t holding things as steady as it should. It’s gradual wear, not a sudden failure, so ask your mechanic how soon it needs doing.
It’s not an emergency, but don’t leave it long. Once the boot splits, grease escapes and dirt gets in, and the CV joint can wear out quickly. Fixing the boot early is usually a much smaller job than replacing the whole CV shaft.
Not always. Reports usually split items into urgent, recommended and monitor. Safety items need doing; others can often wait. At Midas, you won’t find a push to upsell. We’ll tell you what’s urgent and what can wait, and nothing gets done without your OK.
You bet. A good mechanic should be happy to explain every line. At Midas, we’ll walk you through it in plain English before we start any work. It’s all part of the Midas Promise.
This glossary keeps growing, and we add new terms regularly. If yours isn’t here yet, ask your local Midas mechanic. They’ll happily explain it.
