What does Er CO mean?
Communication failure between display board and main control board.
Common causes
- Failed display board
- Failed main board
- Wire harness damage
- Connector issue
Diagnostic & testing steps
- 1. Unplug for 5 minutes
- 2. Check wire harness between boards
- 3. Inspect connectors for corrosion
- 4. Replace display board
- 5. Replace main board if display change doesn't help
Tools required
- Multimeter
- Phillips screwdriver
OEM parts & part numbers
Display Board, Main Control Board, Wire Harness
Part numbers: EBR78940602, EBR84457301
Safety warning
⚠️ Unplug before servicing
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