Mitsubishi Ecodan fault 6
LED4 on FTC is off
Heat pumpWhat it means
LED4 on the FTC control board is off, indicating the SD memory card is either not inserted correctly or not compliant with SD standards.
Likely causes
- Contact failure/short circuit/miswiring
- Fault with outdoor unit transmission/receiving circuit board
- Fault with FTC transmission/receiving circuit board
- Electrical noise causes interference with FTC-Outdoor unit transmission cable
- Outdoor unit abnormal stop
- SD memory card is NOT inserted into the memory card slot with correct orientation
- Not an SD standards compliant memory card
Where to start
- Check the LED display on the outdoor unit circuit board (connect A-control service tool PAC-SK52ST to test; refer to outdoor unit service manual for EA-EC codes)
- Check the connections on the indoor and outdoor units have not become loose and that the connecting cable is not damaged
- Turn the power to the indoor unit OFF and then ON
The full answer, free
- 29 more checks in order
- The readings and component tests from the manual
- How to put it right, step by step
- The manual page for this fault (page 54), right under the answer
Safety: Isolate the outdoor unit and any backup heater, and give the inverter capacitors time to discharge before you open the electrics. Anything on the refrigerant circuit needs F-gas certification.
From the Mitsubishi manual for the Ecodan. Check the model on the data plate before you order parts.
Other Mitsubishi Ecodan fault codes
- 1Main remote controller display is blank
- 10Temperature of DHW tank water dropped
- 12Water leakage
- 13Heating system does not reach the set temperature
- 14In 2-zone temperature control, only Zone2 does not reach the set temperature
- 15When a PUHZ-FRP outdoor unit is connected, DHW or heating operation cannot run
- 16When a PUHZ-FRP outdoor unit is connected and in heat recovery operation, the set...
- 19Water discharges from pressure relief valve (primary circuit)
- 2'please wait' remains displayed on main remote controller
- 20Water discharges from pressure relief valve (sanitary circuit)
- 23Noisy water circulation pump
- 25Mechanical noise heard coming from the cylinder unit
- 26Water circulation pump runs for a short time unexpectedly
- 3Main screen appears then disappears after pressing ON button
- 33L6 error (circulation water freeze protection error) occurs during DHW or LP mode...
- 34The energy monitor value seems not correct
- 4LED2 on FTC is off (FTC powered on independent source)
- 5LED2 on FTC is blinking
- 7No water at hot tap
- 8Cold water at tap
- 9Water heating takes longer
- E0Main remote controller communication failure (reception error)
- E1Main remote controller control board failure
- E2Main remote controller control board failure