Why are Perth summers hard on batteries?
RAC WA says battery life depends on the battery type, how the car is used, and the climate it lives in, with extremely hot weather on its list. Perth has days above 35 degrees on 26 days in an average year and above 40 on 5, and it's hotter again under the bonnet of a car parked in the sun.
Age makes it worse. RAC WA says a battery older than three years is less able to handle extreme weather and may fail sooner, and it suggests checking the battery as the weather heats up. Many modern cars use calcium batteries, which RAC WA says are less affected by extreme conditions.
Signs a battery is on its way out
- The engine turns over more slowly than it used to, especially on the first start of the day.
- A slight clicking just before the engine starts.
- Dash lights or headlights that fade or flicker while you start the car.
- The battery light on the dash, which can also mean a charging fault.
- Scaly build-up on the terminals, or any sign the battery is leaking.
- The car has sat for a couple of weeks or more and starts reluctantly.
Battery jobs around Perth
Stop-start cars and hybrids
RAC WA says AGM batteries suit hybrid and stop-start vehicles, and an AGM should be replaced with another AGM. A car with an EFB battery can take an EFB or an AGM. Some cars also need the electrical system reset when a new battery goes in, called battery registration, so tell the mechanic the exact model.
Cars left parked
Plenty of Perth cars sit for weeks while their owners work away or travel. RAC WA says a car left unused for more than two weeks will likely need its battery looked at, and a daily run won't fully recharge a battery that's been run flat. A proper battery charger will.
The old battery
Lead-acid batteries go to a licensed recycling facility. Ask the mechanic to take the old one with them, so it doesn't end up in the bin.
What you can do, and what to leave to the mechanic
You can
- Note when it's slow to start: first thing, after a hot day, or after the car has sat.
- Check the owner's manual for the battery type the car takes.
- Keep a sunshade in the windscreen and park in the shade where you can.
- Call roadside assistance if the car won't start and you're not confident with jumper leads.
Leave to the mechanic
- Testing the battery and the alternator, so you replace the right part.
- Fitting the correct type and size, and battery registration where the car needs it.
- Jump starts on modern cars: RAC WA warns there's always some risk of electronic damage.
Our take
We'd have a battery that's three or more years old tested in spring, before the first run of hot days, rather than wait for it to strand us in a car park. A test takes the guesswork out: slow starting can be the alternator rather than the battery, and RAC WA says a multimeter test tells the two apart.