Monogram Cooktop Error Code E8 – Coil / Heating Element Circuit Fault
The E8 error code on a Monogram cooktop signals a fault detected in the induction coil or radiant heating element circuit. The control board monitors the current through each heating circuit during operation; when current is absent, asymmetric, or outside expected parameters, E8 is triggered and the affected zone is disabled.
What Causes E8
- Open-circuit induction coil – A wire break in the coil winding interrupts current flow. This is often caused by overheating from prolonged high-power operation or physical impact on the glass.
- Short-circuit in the coil – Shorted coil turns reduce impedance sharply, causing overcurrent that the board detects as abnormal. Heat damage is the typical cause.
- Failed radiant element (radiant models) – On glass-ceramic radiant models, the nichrome heating ribbon can break after thousands of thermal cycles.
- Damaged IGBT driving the coil – If the IGBT module that drives the coil has failed, the coil receives no excitation current, and the board detects an open circuit condition.
- Cracked cooktop glass – A crack that passes through or near the coil can damage coil conductors or shift the coil position, altering its impedance profile.
Diagnosis and Repair
- Identify the affected zone – E8 may specify a zone code on some models (e.g., E8-1 for zone 1). Test each zone individually to isolate the fault.
- Measure coil resistance – With power off and the coil connector disconnected, measure resistance across the coil terminals. Compare to specification (typically 1–5 Ω for induction coils). An open reading (OL) or very low reading confirms coil failure.
- Inspect for visible damage – Look for burn marks, melted wire insulation, or physical damage to the coil assembly beneath the glass.
- Test the IGBT – If the coil resistance is correct but E8 persists, test the IGBT module for the affected zone using the diode test on a multimeter.
- Replace the coil or IGBT – Coil and IGBT replacement requires disassembly of the cooktop bottom panel. This work should be performed by a certified technician due to the high-voltage capacitors present.