Daikin RXM20R Service Manual page 149

RXM20~71R(9) + ARXM25~71R(9) + FTXM20~71R + ATXM25~50R +
FVXM25~50A
Split New Perfera R32
ESIE20-11B – 2022.02
5 Confirm via the service monitoring tool that the DC fan motor assembly
receives an ON signal.
6 Turn OFF the unit via the user interface.
7 Turn OFF the respective circuit breaker.
DANGER: RISK OF ELECTROCUTION
Wait for at least 10 minutes after the circuit breaker has been turned OFF, to be sure
the rectifier voltage is below 10 V DC before proceeding.
8 Disconnect the DC fan motor connector S70 and measure the resistance on
the connector pins shown below. The measured resistance MUST be:
VDC
1
2
3
7
INFORMATION
The measured resistance values may deviate from the listed values due to instability
during the measurements.
DC fan motor resistance measurements
are correct?
Yes
No
9 Turn ON the power of the unit.
10 With the DC fan motor connector S70 disconnected from the main PCB,
measure the voltage on the connector pins 4-7 (= fan motor power supply) on
the main PCB.
Result: The voltage MUST be:
Unit
Class 42~60 + ARXM71R
RXM71R
11 Measure the voltage on the connector pins 4-3 (= fan motor control) on the
main PCB.
Result: The voltage MUST be 15±10% V DC.
Are both measured voltages correct?
Yes
No
12 Measure the voltage on the DC fan motor connector S70 pins 2-4 (= rotation
command) on the PCB.
Result: The measured voltage should be 0~7.5 V DC. It should NOT be 0 V DC.
Comm
4
4
4
4
Action
Continue with the next step.
Replace the DC fan motor, see
procedures" [
Voltage
200~390 V DC
342~408 V DC
Action
Continue with the next step.
Perform a check of the main PCB, see
"Checking
4 Components
|
Resistance
>1 MΩ
>100 kΩ
>100 Ω
>100 kΩ
"Repair
4
150].
4
procedures" [ 135].
Service manual
149