Thermador Cooktop Error Code E033B

E033B indicates that the right ADB has detected a failure in the inductor activation relay, meaning the control board cannot properly connect or disconnect one of the right-side induction coils. This prevents the affected cooking zone from operating safely. The fault points to either a wiring or connection problem between the ADB and the inductor, or a failed relay component on the board itself.

The right-side cooking zones affected by the right ADB should not be used while this fault is active. The relay fault means the system cannot reliably control whether the inductor is on or off, which is a potential safety concern. The unaffected left-side zones may continue to operate normally, but confirm this with a technician before relying on them.

Repair costs depend on whether the fix is a simple wiring correction or requires replacement of the right ADB assembly. Labor and diagnostic fees typically range from $100 to $200, while an ADB board replacement can add $150 to $400 or more in parts depending on the specific model. Getting a diagnostic visit from a Thermador-authorized technician will provide an accurate estimate for your unit.

A knowledgeable DIYer can safely check whether the inductor wiring harness on the right ADB is loose or disconnected, which is the first recommended diagnostic step. However, if the fault is caused by a failed relay or a defective ADB board, those repairs involve disassembling the cooktop and handling high-voltage components, which is best handled by a qualified appliance technician.

A power reset by turning off the circuit breaker for 30 to 60 seconds may temporarily clear the error, but if the underlying fault in the relay or wiring remains, the code will return once the cooktop is used again. A reset alone is not a repair and should not be relied upon as a solution.