Sensing is the brief phase at the start of a wash cycle where your machine measures the size and weight of your laundry load before adding water. When you see “sensing” on your washer’s display, the drum is slowly rotating or shifting your clothes so built-in sensors can determine how much water to use, how long to wash, and how fast to spin. This process typically lasts 20 to 60 seconds, though the machine may continue monitoring as it fills with water over the next several minutes.
What Happens During the Sensing Phase
When you press start, your washer doesn’t immediately flood the drum with water. Instead, it nudges the drum back and forth in short bursts. During these movements, sensors inside the machine measure how much resistance the load creates. A small load of t-shirts moves easily and creates little resistance. A heavy load of towels or jeans pushes back harder against the motor. The washer uses that feedback to calculate your load’s size and weight.
Some machines also trickle in a small amount of water during this phase, wetting the clothes slightly to get a more accurate reading. Fabrics absorb water differently, so this step helps the washer fine-tune its water level. Once sensing is complete, the machine sets its fill level, wash duration, and spin speed, then transitions into the main fill and wash cycle.
Why Modern Washers Use Sensing
Older top-load washers let you manually select the water level: small, medium, or large. Most people just selected “large” every time, wasting water on half-full loads. Modern high-efficiency (HE) washers eliminated that guesswork by automating the decision. The sensing phase ensures the machine uses only as much water as the load actually needs, which reduces both water and energy consumption over time.
Beyond water savings, sensing also protects your machine. During the spin cycle, an unevenly distributed load can cause serious vibration. Research on washing machine sensors has shown that displacement sensors and accelerometers inside the drum can detect imbalance at speeds well below the point where damage occurs. If your washer senses a lopsided load, it may pause, redistribute the clothes with additional tumbling, and try again before ramping up to full spin speed.
How Different Brands Handle It
The core concept is the same across brands, but the marketing names and extra features vary. Whirlpool models use what the company calls Adaptive Wash Technology, which adjusts cleaning action based on load size. Their machines pair load sensors with automatic detergent dispensers that meter out the right amount of soap per load. The approach is straightforward: sense the load, match the water and detergent, wash.
LG takes a more tech-forward approach. Many of their washers use AI-based fabric detection that goes beyond just weighing the load. The system identifies fabric types and automatically selects wash settings it considers optimal for those materials. Samsung offers similar smart-sensing features in its higher-end models. Regardless of brand, if your display says “sensing,” the machine is doing the same fundamental job: figuring out what’s inside the drum before committing to a full cycle.
How Long Sensing Should Take
The initial sensing detection takes 20 to 60 seconds on most machines. However, the washer continues monitoring throughout the fill process, which can stretch to several minutes as water enters and clothes get saturated. During this time, you may notice the drum rotating intermittently, pausing, and rotating again. This is normal. The machine is repositioning clothes and rechecking its readings as water weight changes the load dynamics.
If everything is working correctly, the display should move from “sensing” to “washing” within a few minutes. A load that takes more than 10 to 12 minutes to clear the sensing phase likely has an issue worth investigating.
When Your Washer Gets Stuck on Sensing
A washer that stays in sensing mode indefinitely is one of the more common complaints, and it usually traces back to a handful of causes.
- Faulty lid switch or lock: Top-load washers use a lid switch to confirm the lid is closed before proceeding. If that switch malfunctions or the lid sensor is misaligned, the machine stays in sensing mode because it thinks the lid is open.
- Overloaded or unbalanced drum: If the load is too heavy or bunched to one side, the washer may keep trying to redistribute clothes without ever getting a stable reading. Try removing some items or rearranging the load manually.
- Clogged drain or pump: Blockages in the drain hose or pump can prevent water from entering or exiting properly. The washer detects that water levels aren’t where they should be and won’t advance the cycle.
- Control board glitch: A power surge or software error can freeze the control board mid-cycle. Unplugging the washer for one to two minutes and restarting often clears a one-time glitch. Repeated freezes point to a control board that needs replacement.
If a simple reset and load adjustment don’t fix the problem, the lid switch is the next thing to check. It’s the most common mechanical failure behind a stuck sensing cycle and is relatively inexpensive to replace.
Detergent and Sensor Accuracy
Using too much detergent, or using non-HE detergent in an HE machine, can interfere with your washer’s sensors over time. Excess soap creates buildup inside hoses and on water-level sensors. When those sensors are coated in residue, they send inaccurate readings, which can cause the machine to use the wrong water level or get confused during the sensing phase. Stick to HE detergent in HE machines, and use the amount recommended on the bottle. Most people use far more detergent than necessary, which creates problems that build gradually over months.
Running an empty cleaning cycle with a washer-cleaning tablet or a cup of white vinegar once a month helps keep sensors and internal components free of soap residue and mineral deposits.