Avoiding Battery & Motor Problems in Cold Weather

Kamilya - September 29, 2023

The first harsh frost of the year - you've scraped the frost off your car windows and settled into the driver's seat. But when you try to start the car, the engine remains silent. Now, you're in a tough spot. Most of the time, it's the battery that fails in cold weather, but sometimes there are other motor problems at play. At CARIFY, we provide you with some valuable tips to keep your vehicle ready for winter at all times.

Whether you drive a Volvo, VW, Porsche, or any other car brand, our expert advice will help you stay prepared for the cold season.

Avoiding Battery Problems

When your car won't start, the battery is usually the culprit. That's why it deserves special attention. In winter, having a relatively new and well-charged battery is crucial. However, even then, you may find that the battery doesn't provide enough power to start the engine. The more you try, the more feeble the starter motor sounds. Why does this happen? Cold weather is particularly challenging for a battery: inside, chemical reactions generate the necessary initial spark in the form of electricity for your car. These reactions require external energy in the form of warmth (ectothermy). The colder it is, the less reactive the ions in the battery become. Furthermore, it discharges more quickly due to the continuous operation of additional power consumers and takes longer to recharge from the alternator while driving. Good to know: The average lifespan of a car battery is four to five years. With our tips, you can avoid battery problems in winter.

Check the Battery Status

Before every winter drive, check the battery status. If you have a battery tester or a multimeter, measure the voltage by connecting the red cable to the positive terminal and the black one to the negative terminal. It's best to keep the measuring device handy in the car during winter, just like a set of jumper cables. But even without a meter, you can identify certain warning signs of a weak battery:

  • Flickering interior lights when starting

  • Sluggish and slow-turning starter motor

  • Dimmer dashboard warning lights

  • Weakening headlights when the vehicle is stationary

To ensure that your slightly aged battery can still serve you faithfully in the upcoming winter, have it checked in the garage before the cold season begins. Mechanics can determine whether a recharge will suffice or if a replacement is needed. For non-maintenance-free batteries, check the fluid level and top it up with distilled water if necessary.

Protect the Battery from Cold

Hardly any vehicle is always sheltered from the elements. So, how can you keep the battery warm? Thermal covers are designed to protect batteries from cooling down, but installing them can be complicated. Whether the insulation layer is effective and beneficial is a matter of debate. Nevertheless, it doesn't hurt to make the effort. However, don't forget to remove the battery's winter coat in the spring; otherwise, it could overheat. As an alternative, you can provide external warmth to the battery before starting. There are now battery warmer pads and heating mats available for this purpose. Our extra tip: Place a hot water bottle on the battery for a few minutes before starting.

Avoid Unnecessary Discharge

Starting the engine places a significant demand on the battery in winter. Therefore, city driving places an even greater burden on the battery. Ideally, it recharges itself while driving through the alternator. After 20 to 30 minutes, it should be fully charged if you don't need to stop and restart the vehicle. In winter, more power consumers are active. In addition to lights, the heater, blower, and rear window defroster also consume power. Extras like heated seats increase comfort but come at the expense of the battery. These measures will help ensure that your battery doesn't run down quickly in cold weather:

  • Before starting, do not switch on power consumers like lights, the blower, or the rear window defroster. Instead, depress the clutch and start the car (turn the key only briefly).

  • Avoid unnecessary power consumers or don't use too many of them simultaneously. Especially on short trips, consider turning off the audio system.

  • Never forget to turn off the vehicle's lights after the trip. If they burn for hours, it can lead to deep discharge of the battery. This causes irreversible damage to the battery, and it can no longer function as usual.

  • Keep the battery terminals dry and clean to prevent unintentional discharge due to leakage currents.

  • Grease and tighten the battery terminals with battery grease or petroleum jelly.

If you mostly drive short distances in your car, the battery may struggle to regenerate. The frequent cold starts place a heavy load on it. In that case, you should remove the battery every few weeks and connect it to a charger at home to fully recharge it (maintenance charging).

Avoiding Motor Problems

Not always is the battery to blame for the car's failure to start in cold weather. Sometimes, other motor problems are the cause. We'll reveal what issues your car can face in winter.

Pay Attention to the Right Oil

Always ensure you have enough oil, especially the right type. Like the battery, motor oil is sensitive to cold. It becomes less viscous at sub-zero temperatures and can no longer lubricate the engine effectively. This can lead to engine damage. Winter-grade oils remain supple in cold conditions. It's best to have a seasonal oil change done in the garage. If you want to do it yourself, check the label on the oil container: the SAE class tells you how viscous the oil is at different temperatures. Manufacturers usually recommend a winter oil of the 0W class.

SAE class of engine oilViscosity up to a temperature (in degrees Celsius) of
0W40
5W35
10W30
15W25
20W20
25W15

Check the Coolant Level

Despite freezing temperatures, the engine still needs cooling in winter because it generates a lot of heat during operation. Make sure to add antifreeze to the coolant in time so that the water in it doesn't freeze. Since water expands when it freezes, it can cause the radiator or hoses to burst and, consequently, lead to engine damage. In modern cars, you rarely, if ever, need to top up the coolant. A warning light in the vehicle will alert you to low coolant. However, it's better not to rely solely on that. An occasional check won't hurt. Important: Never pour coolant into a hot engine because:

  • Temperature variations can create cracks in the hoses.

  • The system is pressurized when the engine is hot, and opening the cap can result in scalding.

Wait Until the Engine Warms Up

Outside, a frigid wind is blowing. You're eager for your vehicle to start without any problems and want to hit the road immediately. But for older vehicles, it's not a good idea, as it can strain the engine and battery excessively. In fact, oil and other fluids react to the cold and perform their functions optimally only at a certain temperature, which can take up to 15 minutes in winter. However, you shouldn't let the car idle for that long, as it's not only illegal in Switzerland but can also result in a fine of up to 60 Swiss francs under Art. 42, para. 1 of the Swiss Road Traffic Act if you get caught. The good news is that with newer vehicles, you can generally skip the warm-up process, which helps protect the environment and your wallet. If you drive an older model, we have two tips for you:

  • Starting with a cold engine, you'll reach the operating temperature faster if you drive at lower RPMs.

  • Don't turn on non-essential power consumers until the engine has warmed up.

Additional Tips for Cold Weather

  • Getting stuck in the middle of nowhere in winter is a situation everyone wants to avoid. That's why it's recommended to invest in a power bank for car batteries. It can provide you with a jump start in case of an emergency when no one else is around.

  • Older vehicles are prone to problems like clogged carburetors in winter. To get through the winter without issues, you should identify and address your classic car's weaknesses early on with a winter check-up.

  • Diesel fuel can solidify at temperatures in the single digits Celsius. To ensure your diesel starts smoothly in the cold, use winter diesel with additives that keep the fuel liquid down to -20°C.

  • Cars in garages stay warmer and protected from moisture.

Conclusion: Prevention is Better Than Cure

You can take many steps to prevent motor problems and a failing battery in cold weather. Fill up with cold-weather suitable fluids like oil, coolant, windshield washer fluid, and diesel before the first frost, and have a winter check-up performed. Tip: CARIFY car subscriptions include service and maintenance, including seasonal tire changes.

Whether you drive a Skoda, Renault, Fiat, or any other car brand, ensuring your vehicle is winter-ready is essential for a smooth and hassle-free driving experience.

FAQs:

Is cold weather bad for car batteries?

Yes, at sub-zero temperatures, batteries charge more slowly, and additional power consumers use more energy simultaneously.

Why does a car battery die in winter?

Cold weather reduces battery performance, preventing it from delivering the required energy for starting. For older batteries, even an external charge may not help in the long run.

How long does a car battery last in the cold when the car is idle?

Even when the car is idle, devices like GPS or immobilizers draw power. This causes the battery to discharge within four to six weeks if you don't drive the vehicle. Cold weather reduces battery performance and shortens this span. Tip: Disconnect the battery during longer periods of inactivity.

Why is it difficult to start a cold engine?

Because cold weather makes the engine fluids more viscous, requiring more energy to start. At the same time, battery performance decreases at sub-zero temperatures.

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