U-Line Ice Machine E5: Thermistor 1 Shorted, Reading Invalid
E5 means Thermistor 1 on a U-Line ice machine is shorted, giving the control a value no real temperature could produce. Ice output drops until the sensor circuit is repaired.
What does U-Line ice machine code E5 mean?
When the display of a U-Line UONB115, UHNP315 or UCLR1215 reads E5, Thermistor 1 is shorted. The first temperature sensor is passing a signal that the control interprets as a direct connection between its wires, which no real temperature could cause. Ice output drops until the sensor circuit is repaired. An open circuit on the same sensor is E1 instead, and the display tells us which of the two the control found.
E5 at a glance
- Code
- E5
- Appliance
- U-Line ice machine
- Applies to
- UCLR1215, UHNP315 and UONB115 ice machines from U-Line
- Type
- Needs attention soon
- Can you clear it yourself?
- Sometimes, after the safe checks below
- Most likely cause
- Thermistor 1 has shorted inside its body
What you may notice with E5
- E5 is displayed on the ice machine.
- Ice production drops below the usual amount.
- You may see dampness near the cabinet.
- The machine otherwise keeps its power and lights.
How the ice machine detects E5
A thermistor reports temperature by letting more or less current through as it warms and cools. The control expects the sensor to stay within a believable range. When the sensor, its wire or its plug creates a direct short, the signal collapses to an extreme value that no real temperature in the cabinet could give.
The control recognizes this as an impossible reading and shows E5 for Thermistor 1, the first sensor. Rather than act on a value it cannot trust, it cuts back ice production until the circuit is repaired. The same sensor reading open would show E1 instead. A short can start inside the sensor, along a lead whose insulation has been damaged, or at a plug where moisture or corrosion creates an unwanted path. Testing with a meter shows which one it is, since the cause cannot be judged by sight.
Likely causes of E5
- Thermistor 1 has shorted inside its body
- The wire to the first sensor is pinched so its conductors touch
- Dampness or corrosion at the sensor plug is bridging the contacts
Can you keep using the ice machine with E5?
The machine can stay on while you arrange testing, but it will not make normal amounts of ice. If you find water around the cabinet or smell anything hot, switch it off and unplug it. A moist connector is part of what can cause a short, so keep the area dry. Do not open panels or touch the wiring yourself.
What you can safely check
- Switch the machine off and wait one minute before you look around the cabinet.
- Switch it back on and check the display.
- Look for water pooling near the cabinet and wipe up what you see.
- Make sure the bin door is shut.
- Do not open any panels.
- If E5 returns, contact us.
What our technician does for E5
- Test Thermistor 1 with a meter for a short
- Inspect the lead and plug for a pinch, damage or corrosion
- Check the board input if the sensor tests good
- Replace the part that failed
How to keep E5 from coming back
- Wipe up spills and condensation around the cabinet promptly.
- Keep the machine dry in humid garages and lanai bars where moisture lingers.
- Avoid pinching sensor wires when sliding the machine in and out.
Technical reference
- Code
- E5
- Appliance
- U-Line ice machine
- Control family
- UCLR1215, UHNP315 and UONB115 ice machines from U-Line
- Maker documentation
- U-Line owner manuals and support
- Checked
- November 2026
Code meanings come from the maker’s documentation and our own repair work; we do not reprint the maker’s document. Confirm the full model number before acting on a code. We are an independent repair company, not affiliated with U-Line Corporation.
Related U-Line ice machine error codes
E5 questions
What does it mean when the sensor is shorted?
The sensor is passing signal as if its two contacts were joined directly, so the control sees a value no real temperature could produce and rejects the reading.
How is E5 different from E1?
E1 is the first sensor reading open, while E5 is it reading shorted. The two are opposite problems on a single sensor, and the testing starts at the same place.
Can moisture cause E5?
Yes, damp contacts at the sensor plug can create a shorted reading. For that reason we look over the plug and the wiring first, before we replace the sensor.
Can E5 clear on its own?
A restart can clear a one-off bad reading, especially after moisture dries. A real short brings E5 back, and then the sensor, the wire and the plug need testing to find where the short is.
Is E5 related to a leak?
Not directly. E5 is an electrical reading from a sensor, but water that reaches a connector can cause it. If you find a leak, tell us, because the water source and the sensor plug both matter.
Need help with E5?
A technician finds the cause at your bar or lanai and puts the price in writing before any part comes out.