Indoor Blower Motor - Bosch IDS 2.0 Service Manual

7 0 | Bosch IDS 2.0

13.7 Indoor Blower Motor

Restart unit, give system
call for heating/cooling
Yes
Does blower motor
run properly?
No
No
Is there 230V(AC)
power supply?
Yes
Is there 18-
No
28V(AC) between
CN33 terminals on
IDU control board?
Yes
Is there 18-
No
28V(AC) between
R&C terminals on
IDU control board?
Yes
Is there 18-
No
28V(AC)between Y1&C
terminals on IDU control
board?
Yes
No
Is the LED on the
indoor board ON or
flashing?
Yes
No
Is there 24V(AC)
between the pins at
CN35 on IDU
control board?
Yes
Is there
No
230V(AC) between
CN39 & black wire connected
to transformer?
Yes
Replace motor
Figure 44
Data subject to change
Blower should run any time there is a call for
cooling/heating. Only exception is fan delay
for anti cold air function in heating mode.
No service required
Fix the wire connection or
power supply
Replace transformer
Replace the control board
Fix low voltage
wiring/replace the
thermostat
24V(AC) depends on SW6-1&2 dipswitch fan
speed settings. High or low speed depends on if
Y1 (low) or Y2 (high) call. Measure between
speed pin and C (brown wire).
Replace the control board
Replace the control board
Replace the control board
Tstat Conection
R & C
Y & C
CN33
CN35
07.2021 | Bosch Thermotechnology Corp.
Service Manual
Wire Color
Red & Brown
Yellow & Brown