Refrigerator display shows E01 and unit may not cool properly or may shut down intermittently.

Safety first: Unplug the refrigerator or switch off the dedicated circuit breaker before removing any panels. Electronic boards can carry stored charge; avoid touching exposed contacts.

Steps to check:

• Power reset: Disconnect power for 5–10 minutes, then restore power. If E01 clears and does not return, it may have been a transient glitch.
• Inspect control board connections: Access the main control board (typically behind a rear access panel or at the top of the cabinet). Check all wire harness plugs for full insertion, bent pins, or corrosion. Reseat each connector firmly.
• Check for visible board damage: Look for burnt spots, bulging capacitors, or a burnt smell on the main PCB. Any such signs indicate the board should be replaced.
• Verify supply voltage: With power restored and using a multimeter (only if you are trained and comfortable), confirm correct line voltage is present at the board input. If voltage is unstable or missing, investigate the outlet and house circuit.

When to call a technician: If E01 returns after a reset and wiring is intact, the main control board likely needs replacement and programming, which is best handled by an authorized Thermador technician.