Wolf MDD Three Wavy Lines: In-Use Symbol, Not an Error

What Three wavy lines means

Three wavy lines on a Wolf drop-down door microwave such as the MDD24TE/S/TH or MDD30PE/S/PH is the in-use symbol. It also appears on the SPO speed oven. It tells you the unit is actively working, with microwave energy or a cooking cycle underway. Owners sometimes read it as a warning, but it simply shows that a cycle is running. Our technicians read the code against your model, and that matters for the repair choice.

Common causes of Three wavy lines

Normal in-use indication during cooking
Cycle running or about to finish

✓ One safe check you can try

1. Leave the door closed and let the cycle finish; the symbol clears when it ends. 2. If you did not start anything, press Off or Clear and check the display. 3. Open the door only after the cycle stops. 4. If the symbol shows with no cycle running, call us.

! Why to stop there

The symbol is normal during use and needs no repair.
A symbol stuck on with the unit idle suggests a control matter we can inspect.
Repairs are guaranteed on workmanship for 30 days.

Opening a panel yourself does not automatically cancel a manufacturer warranty, but it can cause accidental damage, and some manufacturers set their own service conditions. Check your warranty terms, or ask us, before deciding.

→Same appliance

Other Microwave codes

No displayWolf Microwave Drawer No Display: Power, Breaker, Noise Filter iWolf MDD Information Cue i: Press Settings for Tips and Weight Range AH SensorWolf Microwave Drawer Code AH Sensor: stops after 16 seconds with ERROR DoorWolf Microwave Drawer Code Door: Drawer Will Not Open or Close Fire SenseWolf Convection Microwave Code Fire Sense: Fire Detected, Shutdown Monitor SwitchWolf Microwave Drawer Code Monitor Switch: Monitor Fuse Blown at Plug-In No-HeatWolf Drop-Down Door Microwave Code No-Heat: door not latching TCOWolf Microwave Code TCO: thermal cutout open, unit dead

Three wavy linesThree wavy lines questions

What are the three wavy lines?

They are the in-use symbol on MDD microwaves and the SPO speed oven. They show that a cooking cycle is active. Knowing Three wavy lines saves guessing at the start, so nothing is replaced on a hunch.

Should I be worried when I see them?

No. It is information, not an error. It goes off when the cycle ends or you press Off. Seeing Three wavy lines narrows the search considerably, and then we outline the options.

What if they stay on when nothing is cooking?

That is unusual. Switch the breaker off for a minute. If the symbol returns while idle, call us for a check and a written quote.