warning Honeywell

Error Code unlock

Keypad lockout is active — the display shows 'unlock' when the keypad is locked and temperature settings cannot be changed.

? What Causes This

Keypad lockout has been enabled (set to PART or ON) to restrict thermostat access.

How to Fix It

  1. Press the CENTER button and enter the default password
  2. Press up or down arrows to change each digit.
  3. Press Select after each digit.
  4. Once all four digits are entered, press Select again to unlock.
  5. To disable lockout, press Menu > down arrow to LOCK > Select > OFF > Select.

Source: page 5 of the official manual

From the manual

Manual page 5 — Honeywell error unlock

This error code appears in:

Honeywell T4 Pro Thermostat