Display shows E1 and the coffee maker will not start a brew cycle.

Safety first: Unplug the coffee maker before inspecting or moving parts. Never work on the unit while it is hot or connected to power.

Step-by-step checks:

• Reseat the water reservoir: Remove the reservoir completely, empty and rinse it, then firmly reinstall it so it sits flat on the base. Many Chefman coffee makers use a small magnet/float in the reservoir that must align with a reed switch in the base.
• Check the float: Gently shake the reservoir and look for a small plastic float inside. Make sure it moves freely and is not stuck with scale or debris. If stuck, soak the reservoir in a 1:1 white vinegar and water solution for 20–30 minutes, then rinse thoroughly.
• Clean the reservoir base area: Wipe the base contacts and sensor area with a dry cloth. Do not pour water directly into the base. Ensure there is no coffee residue or mineral buildup where the reservoir sits.
• Power reset: With the unit unplugged, press and hold the main power or brew button for 10–15 seconds to discharge residual power, then plug back in and test.
• If E1 persists: The internal reed switch or the control board sensor circuit may be faulty. Replacement of the reservoir presence sensor/reed switch assembly or main control PCB is typically required and is best done by a qualified technician.