It feels backwards, but heat does more long-term damage to a car battery than cold does. Cold weather just exposes a battery that's already weak. In South Florida, months of high temperatures under the hood are what wear it down in the first place.
Why heat wears batteries out
A car battery makes power through a chemical reaction. High temperatures speed that reaction up, which also speeds up the wear inside the battery. Heat can also evaporate fluid and encourage corrosion on the terminals. The result is a battery that loses capacity faster than it would in a cooler climate, and often fails without much warning.
Warning signs your battery is on its way out
- The engine cranks slowly, especially after the car sits overnight
- You hear clicking when you turn the key
- The battery light or check engine light comes on
- Headlights dim when the engine idles
- White or blue crust builds up on the battery terminals
- The battery case looks swollen or bulging
- You've needed a jump start more than once recently
How to get more life out of your battery
- Have it tested once a year after it's two years old. A load test shows how much life is left.
- Keep the terminals clean and tight. Corrosion blocks the flow of power.
- Park in the shade or a garage when you can.
- Avoid lots of very short trips. They don't give the alternator time to recharge the battery.
- Don't leave accessories running with the engine off.
Battery dead? Don't call a tow truck first
A car that won't start is the one problem you can't drive to a shop. We come to wherever the car is parked, test the battery, the alternator and the starter, and replace only what's actually bad. If the battery keeps dying after a jump, we check for a charging problem or a drain before selling you a new battery.