Display shows E4 and smoker runs but temperature is inaccurate or fluctuates wildly.

Safety first: Unplug the smoker and allow it to cool.

• Locate secondary sensor: Some Cuisinart electric smokers use a second sensor near the top vent or control housing. Refer to your model’s layout and locate this probe.
• Clean sensor: Wipe the sensor tip with a soft cloth and food‑safe degreaser to remove buildup that can cause false readings.
• Check mounting: Ensure the sensor is firmly mounted and not dangling or touching metal surfaces that could skew readings.
• Inspect wiring and connector: Verify the harness is intact and the connector is fully seated on the control board. Repair any frayed or pinched wires.
• Replace if needed: If cleaning and reseating do not resolve E4, replace the ambient/secondary temperature sensor with a compatible Cuisinart part.