Bosch Error Codes

Bosch Climate units (CL3000i / CL5000i / Multi) share much of the Midea code map; controller shows E/P/F codes.

Code	Description	Likely cause	Recommended action
E0	Indoor unit EEPROM error	Indoor PCB memory fault	Replace indoor PCB.
E1	Indoor ↔ outdoor communication error	Comms wiring or PCB fault	Check S/N interconnect; replace PCB if needed.
E2	Zero-crossing signal error	Mains supply / indoor PCB	Check supply and indoor PCB.
E3	Indoor fan speed out of control	Stalled / failed fan motor	Test motor and capacitor / driver.
E4	Indoor room sensor (T1) fault	Open / short T1 sensor	Replace T1 thermistor.
E5	Indoor coil sensor (T2) fault	Open / short T2 sensor	Replace T2 thermistor.
E6	Outdoor unit malfunction	Outdoor protection active	Read outdoor LED for sub-fault.
E8	Display PCB communication error	Display ribbon / PCB	Re-seat ribbon, replace display.
P0	IPM module protection	Overcurrent / IPM failure	Megger compressor, replace inverter.
P1	Over / under voltage protection	Mains supply out of range	Measure supply voltage.
P2	IPM over-temperature	Heatsink too hot	Clean heatsink, check fan and paste.
P4	Inverter compressor drive error	Inverter PCB fault	Replace inverter PCB.
P5	Outdoor fan speed out of control	Stalled / failed outdoor fan	Test fan motor and driver.
P6	Low-pressure protection	Undercharge / blocked filter	Leak test and recharge.
F1	Outdoor ambient sensor fault	Open / short OAT sensor	Replace OAT thermistor.
F2	Condenser coil sensor fault	Open / short coil sensor	Replace condenser thermistor.
F3	Discharge pipe sensor fault	Open / short Td sensor	Replace discharge sensor.

Indoor unit EEPROM error

Cause:: Indoor PCB memory fault
Action:: Replace indoor PCB.

Indoor ↔ outdoor communication error

Cause:: Comms wiring or PCB fault
Action:: Check S/N interconnect; replace PCB if needed.

Zero-crossing signal error

Cause:: Mains supply / indoor PCB
Action:: Check supply and indoor PCB.

Indoor fan speed out of control

Cause:: Stalled / failed fan motor
Action:: Test motor and capacitor / driver.

Indoor room sensor (T1) fault

Cause:: Open / short T1 sensor
Action:: Replace T1 thermistor.

Indoor coil sensor (T2) fault

Cause:: Open / short T2 sensor
Action:: Replace T2 thermistor.

Outdoor unit malfunction

Cause:: Outdoor protection active
Action:: Read outdoor LED for sub-fault.

Display PCB communication error

Cause:: Display ribbon / PCB
Action:: Re-seat ribbon, replace display.

IPM module protection

Cause:: Overcurrent / IPM failure
Action:: Megger compressor, replace inverter.

Over / under voltage protection

Cause:: Mains supply out of range
Action:: Measure supply voltage.

IPM over-temperature

Cause:: Heatsink too hot
Action:: Clean heatsink, check fan and paste.

Inverter compressor drive error

Cause:: Inverter PCB fault
Action:: Replace inverter PCB.

Outdoor fan speed out of control

Cause:: Stalled / failed outdoor fan
Action:: Test fan motor and driver.

Low-pressure protection

Cause:: Undercharge / blocked filter
Action:: Leak test and recharge.

Outdoor ambient sensor fault

Cause:: Open / short OAT sensor
Action:: Replace OAT thermistor.

Condenser coil sensor fault

Cause:: Open / short coil sensor
Action:: Replace condenser thermistor.

Discharge pipe sensor fault

Cause:: Open / short Td sensor
Action:: Replace discharge sensor.

For field guidance only. Codes and procedures vary by model and firmware — always confirm with the Bosch service manual for the specific unit before carrying out a repair.

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