E4 error appears during pressure cooking; cooker may not build pressure or may stop mid-cycle.

Safety first: Unplug the cooker and fully release any pressure before disassembling the lid. Keep face and hands away from the steam release path.

Cleaning the pressure path:

• Remove the steam release valve and anti-block shield (small metal or plastic cap over the steam outlet) from the lid.
• Clean all holes and channels with a small brush or toothpick. Rinse and dry thoroughly.
• Check the float valve and its silicone cap for free movement and cleanliness.

Pressure sensor port (advanced):

• On many T-fal multicookers, a small channel from the lid interior leads to a pressure sensor on the lid PCB or via a silicone tube to the main body.
• Inspect this port or tube for blockage by dried food or scale. Carefully clear any obstruction without enlarging the hole.
• Check the silicone tube (if present) for cracks or disconnection.

If cleaning does not resolve E4, the pressure sensor or main control board may be defective and should be replaced by a qualified technician.