The first thing a good technician does on an induction service call costs nothing: they grab a magnet and touch it to the bottom of your pan. Induction heats the cookware directly through a magnetic field, so a pan that is not magnetic simply does not register. It sounds basic, but a new aluminum skillet or a stainless pan without a magnetic base has fooled plenty of owners into thinking a zone had died.
Once cookware is ruled out, the diagnosis follows a fairly predictable path. Knowing what gets tested, and why, makes it easier to understand the quote you receive and whether repair is worth it.
How the cooktop is built
Under the glass are a few main parts:
- Induction coils, flat copper windings under each cooking zone.
- Power boards, sometimes called generator or inverter boards, which turn household power into the high-frequency current that drives the coils. One board often runs two zones.
- A touch control or user interface board under the glass where you tap the controls.
- Temperature sensors beneath each zone that watch for overheating.
- One or more cooling fans that pull air across the electronics.
The glass itself is a ceramic top that does not generate heat. It only gets hot from the pan sitting on it.
Pan detection is built into the power electronics. When you set a pan down, the board senses whether there is enough magnetic material over the coil to heat. A pan base much smaller than the marked ring, a warped bottom that rocks, or a pan pushed off center can all lead to a blinking zone symbol and no heat. That is the cooktop protecting itself, not a failure, and it is worth ruling out before booking a visit.
What the technician measures, in order
1. Supply power
Most induction cooktops run on a dedicated 240-volt circuit. If one leg of the supply is missing, some zones or the whole cooktop may act dead or throw errors. The technician checks voltage at the connection before suspecting anything inside, which is also why a half-tripped double breaker is the first thing to rule out.
2. Error history
Many models store fault codes or have a service mode that shows them. The code tells the technician which circuit to test. It narrows the search but does not always identify the failed part on its own.
3. Cooling fan
Induction electronics produce real heat. If the fan is seized or the intake is blocked, the cooktop protects itself by reducing power or shutting zones off mid-cook. Fans are among the more affordable repairs, and blocked airflow is a common installation issue when a drawer or stored items sit right under the unit.
4. Temperature sensors
Each sensor changes its resistance with temperature. A technician compares the reading with what it should be at room temperature. A failed sensor can make a zone shut off early or refuse to start.
5. Coil and wiring
Coils are checked for continuity and for any short to the chassis. Coil failures are less common than board failures, but spills that seeped through a crack or worn seal can damage them.
6. Power board and touch control
If power, sensors, fan and coils check out, attention moves to the boards. A failed power board typically kills the pair of zones it drives. A failed touch control can make the whole surface unresponsive or cause phantom key presses. These boards are the most expensive common parts on an induction cooktop.
Safety: what not to do yourself
Induction power boards contain capacitors that can hold a dangerous charge for some time after the power is switched off. Do not remove the cooktop from the counter, open the underside or touch the boards. What you can do safely:
- Try a pan you know is magnetic and centered on the zone.
- Check that the control lock or child lock is not on.
- Wipe the control area dry; water on the touch panel can make it ignore input or shut down.
- Reset the breaker once if the cooktop went dark after a storm.
- Look underneath through the cabinet for blocked vents, and move stored items away.
If the glass is cracked or you smell burning electronics, turn the breaker off and keep it off.
Turning test results into a decision
A fan, a sensor or a single power board on a cooktop in good condition is generally worth repairing, because induction units are expensive to replace and the coils and glass tend to last. The math tips the other way in a few situations:
- The glass is cracked and a board also failed, often because a spill reached the electronics.
- The manufacturer no longer supplies the power or control board for that model.
- More than one board needs replacing on a unit that is already many years old.
Brand matters for parts. European makers like Bosch and Miele offer good induction parts support, but some components can take longer to arrive than common domestic parts. If glass is the main issue, our guide to cracked cooktop glass explains the options.
What happens at the visit
ProFix Appliance Repair Charlotte services induction, radiant and gas cooktops from all major brands. The technician runs these tests, explains which part failed and gives you the repair price before starting, and if a part has to be ordered you will know that up front. Repairs carry a 90-day parts and 30-day labor warranty. Book online or call us to set up cooktop repair.