Samsung’s range and wall oven code article carries a short section of displays that are not errors, and the one that causes the most alarm is tESt, which the seven-segment display can also render as tE5t. Samsung’s definition is plain: the range is in Demo mode, and the oven and cooktop will not heat. Demo mode lets a range light its controls on a sales floor without heating anything, and it stays available on the range you bought. It gets switched on by a button combination held for a few seconds, which is easy to do while cleaning the panel, and it survives a power cut, so a range that came back from an outage showing tESt was in Demo mode before the outage.
Turning It Off
Samsung’s instruction is to consult the user manual for the steps to disable Demo mode on your model, and that is the right first step rather than trying combinations. On most Samsung ranges the exit is a hold of a named pair of buttons for several seconds until the display changes; the pair differs between gas, electric and induction models and between control generations. Once out of Demo mode, set the oven to a low bake and confirm the element or burner comes on within a minute or two. If the display refuses to leave tESt after the manual’s combination is tried carefully twice, the control is not registering the buttons and that is a problem for a visit.
C to P: Cooktop in Use
The second non-problem is C to P, which appears when you try to start Self Clean while a cooktop burner or element is on. Samsung’s meaning is that one or more cooktop burners or elements are active, and its instruction is to turn all burners or elements off, after which Self Clean will run. On an induction model a zone that is switched on but has no pan on it still counts as active. Owners see the letters and assume a part code; it is the range refusing to lock its door and heat to cleaning temperature while the top is in use.
The Underlined u
On induction ranges a small underlined u over a zone is what Samsung calls a pan detection error: the cookware on that zone is not suitable in size, material or placement, so the zone will not heat. A pan that is not magnetic, a pan much smaller than the zone, or a pan sitting off-center all trigger it. Move or change the pan and the u clears; it is a notice, not an error, and it has its own post on this site under cooktops.
Hot Surface and Lock Indicators
Two other lights are worth naming so they are not mistaken for codes. A hot-surface indicator stays lit after a radiant or induction zone is switched off until the glass has cooled, and on some models the display shows a word or symbol for it; it is a warning about the glass, not about the range. A padlock icon with an unresponsive panel is Child Lock, which Samsung’s icon guide says will cause the panel not to respond until it is turned back off, by a button hold named in the manual.
When the Display Shows Something Else
Real Samsung range codes are C-numbered, such as C-10, C-24 and C-F0, or plain words such as door and bAd LinE, and those are covered in their own posts here. The non-problem displays above have one thing in common: the range is working exactly as designed and telling you why it is not doing what you asked. If a range that has left Demo mode still does not heat, or if tESt appears on its own without anyone touching the panel, book a Samsung range repair and say what the display shows and what the manual’s combination did.