Range or cooktop display shows a generic 'Err' message when attempting to set temperature or power.

Safety first: If any burning smell or abnormal noise is present, disconnect power immediately.

• Reset control: Turn off power at the breaker for 2–3 minutes, then restore power to reset the electronics.
• Check user input: Ensure you are following the correct sequence for your Gram model (e.g. select function, then temperature). Remove any meat probe or accessories and try again.
• Inspect knobs and buttons: Verify that no knob is between positions and that all buttons move freely. Clean the control panel surface and dry thoroughly.
• Service mode: Some models allow entering a diagnostic mode to clear stored errors; refer to the service documentation.
• Board replacement: If Err persists with correct operation and no stuck keys, the control board may be defective and require replacement.

Warning: Do not repeatedly cycle power rapidly; allow a few seconds between off and on to protect electronics.