E4 error appears and the multicooker stops heating, often during pressure cooking.

Safety first: Allow the cooker to fully depressurize and cool. Unplug before inspection.

• Clean pressure path: Remove the inner lid and clean the steam release valve, anti-block shield, and pressure regulator components according to the Bosch manual. Food residue can block the pressure sensor port.
• Check steam valve: Ensure the steam release knob or slider moves freely between positions and is not clogged with starch or fat.
• Inspect sensor port (advanced): On some Bosch models, a small channel from the lid or top of the pot leads to the pressure sensor. Use a thin, non-metallic brush or pipe cleaner to gently clear any blockage.
• Check wiring: With the top or bottom cover removed (depending on model), verify that the pressure sensor connector is firmly attached to the control board and that no wires are damaged.
• Replace sensor if needed: If cleaning and reseating connectors do not clear E4, the pressure sensor module should be replaced with a Bosch-compatible part.