Wolf Module Cooktop Code E26: Zero cross signal missing

What E26 means

On Wolf integrated module cooktops from the 2015 series, such as the SM15TF/S and TM15TF/S, E26 means the zero cross input signal is not present. The control uses that signal to time power to the heating circuits, and without it, it cannot switch loads safely. The display shows E26 and the cooktop stops heating. The cause is in the power board or its supply, or in the incoming power.

Common causes of E26

Power board not producing the zero cross signal
Incoming power to the cooktop unstable or incomplete
Control board that cannot read the signal

✓ One safe check you can try

1. Turn all modules off. 2. Check whether other appliances or lights in the home are affected, which would point to a house power problem. 3. Pause the circuit at the breaker for a full minute and then re-energize it. 4. If E26 returns, stop and call us; do not open the cooktop.

! Why to stop there

This signal times the switching of heating power, which we only test with meters and live access.
If the cooktop supply is the problem, an electrician may be involved too.
We never start on a verbal price; the written quote comes first and our work is warranted 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.

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Other Cooktop codes

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E26E26 questions

What is a zero cross signal?

It marks the point where alternating current passes through zero volts. The control uses it to time switching, and E26 means that signal is missing.

Can the wall breaker be the cause?

A breaker or supply problem can remove the signal. We check the supply at the cooktop first, then the board, so you do not pay for the wrong repair.

Is it safe to try again?

One breaker reset is fine. Repeated attempts will not help and are not recommended, since the control cannot switch heating loads safely without the signal.