U03 appears and the cooker cancels the program shortly after starting.

Safety first: Unplug the cooker and allow it to cool before opening the lid.

• Check recipe liquid: Ensure you are using enough liquid for pressure cooking (typically at least 1–2 cups depending on Brock model).
• Avoid thick sauces initially: For thick sauces or stews, start with more liquid and thicken at the end of cooking to prevent rapid localized overheating.
• Clean steam path: Remove and clean the steam release valve and anti-block shield to ensure proper venting.
• Reduce fill level: Do not exceed the MAX line, and for foamy foods (beans, grains) fill only to 1/2–2/3 of the pot.
• Test with water only: Run a short pressure cycle with just water. If U03 still appears, the pressure sensor or control logic may be faulty and require service.