Power Transistor Check - Daikin RXQ12AHR Service Manual

Check
6.4

Power Transistor Check

CHECK 4 Perform the following procedures prior to check.
(1) Power OFF.
(2) Remove all the wiring connected to the PCB where power transistors are mounted on.
Preparation
Multimeter
Point of Measurement and Judgment Criteria
Turn OFF the power supply. Then, after a lapse of 10 minutes or more, make measurement of
resistance.
When using the analog type of multimeter,
make measurement in resistance measurement mode in the x1 k range.
No.
10
11
12
When using the digital type of multimeter, make measurement in diode check mode.
No.
10
11
12
290
Measuring point
Judgment
Criteria
+ –
1 P2 U
2 P2 V 2 ~ 15 k
3 P2 W
4 U P2
5 V P2
15 k and
6 W P2
7 N3 U
(including  )
8 N3 V
9 N3 W
U N3
V N3 2 ~ 15 k
W N3
Measuring point
Judgment
Criteria
+ –
1 P2 U
2 P2 V
1.2 V and more
3 P2 W
4 U P2
5 V P2
6 W P2
0.3 ~ 0.7 V
7 N3 U
8 N3 V
9 N3 W
U N3
V N3
1.2 V and more
W N3
 Prepare the analog type of multimeter.
For the digital type of multimeter, those with
diode check function are available for the
checking.
Remarks
―
Due to
condenser
charge and so
on, resistance
more
measurement
may require
some time.
―
Remarks
Due to
condenser
charge and so
on, resistance
measurement
may require
some time.
―
Due to
condenser
charge and so
on, resistance
measurement
may require
some time.
SiAF341904E
Part 6 Service Diagnosis