Bosch BMS500-AAU036-1AHCXC - Outdoor Fan Speed Malfunction (EC 07;EC 71)

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Service Manual
Bosch Climate 5000 Series Ductless Air Conditioner / Heat Pump Multi Zone Outdoor Units (01.2023)
8.6.7 Outdoor fan speed malfunction (EC 07) Over current failure of
outdoor DC fan motor (EC 71)
Error Code EC 07/ EC 71
Malfunction decision conditions
When outdoor fan speed keeps too low (300RPM) or too high(2400RPM) for certain time, the unit will
stop and the LED will display the failure.
Supposed causes
f Improper / Incorrect Wiring
f Faulty Fan assembly
f Faulty Fan motor
f Outdoor PCB faulty
Table 37
Troubleshooting:
Figure 67
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Power off, then restart the
unit 3 minutes later. Is it still
displaying the error code?
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Shut off the power supply,
rotate the fan by hand. Does
it rotate properly?
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The unit operates normally.
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Find out the cause and
have it solved. For
example, check whether
the fan is blocked or the
screws which secure the
fan are ght.
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Check the wiring of fan
motor. Are all the
connections good?
No
Yes
No
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Correct the connections.No
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Replace the fan motor
Yes
Yes
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Replace the No
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x
1
?
Check whether the outdoor PCB
is normal through index 1?
Yes
No
outdoor PCB