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