Bosch Climate 5000 Series Service Manual page 43

Service Manual
8.6.3 IPM / outdoor PCB communication error (E3)
Error Code
Malfunction decision conditions
Supposed causes
Table 21
Troubleshooting:
Figure 46
Bosch Thermotechnology Corp. | 08.2020
Bosch Climate 5000 Series Ductless Air Conditioner / Heat Pump Multi Zone Outdoor Units | 43
E3
PCB main chip does not receive feedback from IPM module for 60 seconds.
Improper / Incorrect Wiring
IPM faulty
Outdoor PCB faulty
Communication malfunction between
IPM board and outdoor PCB
Is there at least one LED in
the IPM board lit?
No
Check the signal wire between
the IPM module and the PCB.
No
Reconnect and retry. Is the
error still displaying?
No
Replace IPM board, and
then check whether the
system can run normally
No
Replace outdoor
PCB, and then check
whether the system can run
normally
No
Replace the electric control
box
Yes
Yes
No
Yes
Yes
Problem is solved
Data subject to change