System Diagnosis
Inverter Module Protection
Troubleshooting guide for the York Default system fault EB.
Loss of comm LEDs, incorrect polarity, or a fault that appears only when indoor and outdoor boards talk.
Board swaps without harness checks can hide the real fault if the wiring path is damaged.
Use the ACLogics AI assistant to walk through this error code step-by-step.
Upload nameplate & symptoms
AI isolates the likely default branch behind code EB
Document the verified result and next action