What Does The REST Button Do In VW Cars? (And When Should You Use It?)

If you've ever glanced over the climate control panel on your Volkswagen car, you may have noticed a mysterious "REST" button, usually close to the recirculation button. As cool as it would be, it doesn't send your car into some form of a power-saving sleep mode — but the function it performs isn't far off. The REST button is designed to keep your car's interior warm, even after the engine has been turned off. 

Normally, your car's heater stops blowing hot air as soon as you kill the ignition. With the REST mode activated, your car will circulate the residual heat from the engine through the cabin's heater core, and with the fan that's powered by the battery, warm air will continue flowing into the car. This is an excellent use of thermal energy that's left over, which would otherwise be expelled through the radiator. 

You will also notice that pressing the REST button while your car is still running will do nothing — it requires the engine to be turned off. Since this functionality relies on the residual engine heat and your car's battery to power the pump and the fan, it doesn't work indefinitely. You can expect this mode to keep your car actively warm for around 15 to 30 minutes at a stretch.

The REST feature isn't exclusive to Volkswagen cars, you can also find it in certain BMW models. You should find most relatively modern VW cars equipped with this functionality — but that shouldn't be a reason not to steer clear of certain Volkswagen used models. When activated, you can even adjust your car's cabin temperature with the climate control knobs to find the sweet spot.

As for why or when you would want to activate the REST mode on your car, it's best explained as a feature that helps maintain your car's cabin temperature in colder climates for short bursts of time. Perhaps you're parked outside your friend's house waiting for them to hop in — instead of idling your car just to avoid freezing yourself, the REST button will leverage residual heat from the engine. 

This could come in handy if you've stepped outside your vehicle to run a quick errand, and want it to be nice and warm when you return. Beyond the immediate luxury that it provides, the REST mode helps avoid unnecessary idling, which directly contributes towards fuel savings and better engine care to keep it running long-term. If you are unsure whether your Volkswagen car features the REST functionality, you can look for it in the owner's manual.