d4
Invalid memory-card data (outdoor unit)
This code typically points to
- Shared data set on memory card rejected by outdoor integrated control module
Next checks to confirm
- Verify shared data set is correct for specific outdoor unit model
- Repopulate using correct memory card if required
Escalation
Outdoor unit operation different than expected or inhibited until valid shared data is accepted
Reset behavior
Error clears once valid data is loaded and power is cycled per procedure.
Urgent
Fix now