Top Car Breakdown Causes (And How To Prevent Them!)

Good vehicle care is essential to keep both you and other drivers safe on the road. A bit of consistent maintenance can save you money, and help to avoid breakdowns and potentially devastating crashes. Canstar reveals some of the most common breakdown causes that you need to be aware of before hitting the road this winter.

Breakdown causes: battery faults

Battery faults are one of the most common causes of breakdowns. If you have a problem with your battery, you’ll probably have trouble starting your car. A car’s battery powers the starter motor, then the engine turns the alternator, which recharges the battery. Having a flat battery is commonly caused by leaving your lights on when the engine’s off. There’s also a chance, however, that battery problems are a result of lots of short journeys, plugging in a lot of gadgets, such as phones, or a poor electrical connection. Old batteries are more prone to failure, especially in cold winter weather.

How to prevent them

The easiest way to keep your battery in good working order is to remember to switch everything off when you get out of your car, and to have it regularly serviced. Removing the key from the ignition might not turn off the lights automatically, so always remember to do a quick check. Some more modern cars will automatically turn off the lights, so make use of that setting if it’s an option.

When you take your car for a service, the mechanic should check the battery connections are secure and the battery terminals are free from corrosion. Always aim to replace your battery before it lets you down, most last about four to six years. To be on the safe side, it’s advisable to carry a pair of jump leads in your boot, should you need a jump-start (or to help another driver in distress!). If you can afford one, a portable jump-start battery is also handy to keep in your car; prices start around $200. 

Breakdown causes: tyre issues

Punctures are a pain and are often caused by hitting a sharp object, but they can also appear as a result of things such as the tyre hitting the kerb or a deep pothole; age of the tyres if the tread is worn; or the tyre’s valve (where the air is pumped in) becoming damaged. If you hit anything on the road that you think may impact your tyres, check your wheels and rims. Speak to a specialist tyre dealer as soon as you can if you spot any damage, especially bulges in the tyre wall.

How to prevent them

Check your tyre pressure and tread regularly. If you drive with heavy loads, adjust your tyre pressure to cope. Avoid driving over large potholes on the road, (and obviously) sharp objects if you can see them coming. Of course, plenty of times, you can’t!

Breakdown causes: engine oil problems

Having the wrong level of engine oil can damage your engine and cause breakdowns. Having too much oil is just as risky as having low oil. Always check the owner’s manual of your car to find out which kind of oil your car takes. Signs your engine oil is low could include an engine oil pressure warning light on your dash; overheating; a knocking sound on the engine when it’s running or on startup; loss of power.

How to prevent them

Regularly check your engine oil using the dipstick – the level should be between the two lines. (If your vehicle has been running, allow a few minutes for the oil to settle). If the level is low, remove the cap and add a small amount of oil using a funnel. If you’ve been keeping on top of your oil-level checks, you shouldn’t need more than a litre. Your car manual will give you the correct oil specification.

Breakdown causes: overheating

Overheating is another main cause of breakdowns. If your temperature warning light is on, there could be an issue with the engine or the cooling system. It could be a number of things: a blocked radiator, a sudden or gradual loss of water or a faulty thermostat. If there’s steam coming from your engine or the temperature warning light is on, pull over in the nearest safe spot and call for help.

How to prevent it

Regularly check and top up your coolant. Coolant in your radiator stops your engine overheating. If the coolant looks rusty, get it changed. When you remove the radiator cap, the fluid level should be near the top. Coolant is either green or pink coloured. The two should never be mixed, but both can be topped up with plain water, the AA recommends. 

Breakdown causes: fuel problems

Put the wrong fuel in your engine? It happens to more people than you’d think. Don’t start your engine if you’ve put petrol in a diesel or vice versa. Just push your car off the forecourt to a safe place and call roadside assistance for some help.

How to prevent it

It’s an easy mistake to make if you’re not paying attention. Just always double-check the pump nozzle before you pull the trigger. They are always clearly labelled at the pump. The diesel nozzle is also larger, so it can be harder to fill a petrol vehicle with diesel by mistake.

Breakdown causes: alternator troubles

Alternators are used in modern cars to charge the battery and power the electrical system when the engine is running. The alternator light coming on can indicate a wiring fault, loose connection or charging system failure. A range of things can trigger it, so the issue needs to be correctly diagnosed by a professional.

How to prevent it

Keep an eye out for signs your alternator isn’t working as it should. These include: electrical components in the car slowly starting to show signs of failure, like the headlights and dashboard lights dimming; a growling or whining noise; and, of course, the ALT (or GEN) light appearing. There’s a running theme here: keep an eye on things that don’t seem normal in your car, and give it regular check-ups and a bit of TLC to keep it in good running order.

Are you insured?

Some policies will cover you for mechanical breakdowns on the road. Often a breakdown service will be an optional extra to add on to your policy. If you ever need help with things like changing a tyre, jump starts or, a classic, getting into your car if the keys are locked inside, knowing your have 24-hour roadside assistance can be a real lifesaver, especially in the middle of a cold, dark NZ winter.

If you’ve not checked your car insurance recently to see what level of cover you’re paying for, while you’re at it, it’s a good idea to consider if you’re also paying too much and not getting value for money.