E20
Ohme Display / HMI Communication Fault

Ohme charger shows E20; app may indicate 'Display error' or 'HMI fault'. Screen may be blank or frozen.

Advertisements

Safety Warning

This repair may involve working with high voltage components or water connections. Always unplug the appliance before removing any panels.

If you are not confident in your ability to perform this repair safely, we strongly recommend contacting a professional technician.

Advertisements

Possible Causes

Loose display ribbon cable, Failed LCD/OLED display module, Faulty HMI microcontroller, Firmware mismatch between HMI and main board

How to Fix / Troubleshooting

Note: Charging may still function if the app can control the charger.

  • 1. Test via app: Try starting and stopping a charge using the Ohme app. If this works, the fault is likely limited to the display/HMI.
  • 2. Power reset: Turn off the charger at the isolator for 1 minute, then back on. Observe whether the display shows any startup logo or text.
  • 3. Check for backlight: In a dark environment, look closely to see if the display backlight is on but no text is visible, indicating a data issue rather than power.
  • 4. Technician repair: A technician can open the unit, reseat or replace the display ribbon cable, and if necessary replace the display module or HMI board.
Advertisements

Repair Difficulty

Medium 3/5

Required Part

Front Display / HMI Module
Check Price on Amazon

We may earn a commission from links on this page.

Advertisements