Daikin FTXS30HVJU, Service Manual

Page: 118 / 202

SiUS04-924 Check
Service Diagnosis 111
5.1.10 Capacitor Voltage Check
Check No.12 Before this checking, be sure to check the main circuit for short-circuit.

Checking the capacitor voltage

With the circuit breaker still on, measure the voltage according to the drawing of the model in
question. Be careful never to touch any live parts.
5.1.11 Power Transistor Check
Check No.13

Checking the power transistor

Never touch any live parts for at least 10 minutes after turning off the circuit breaker.

If unavoidably necessary to touch a live part, make sure the power transistor's supply voltage is
below 50 V using the tester.

For the UVW, make measurements at the Faston terminal on the board or the relay connector.
OL lead wire
Thermistor lead wire
Fan motor lead wire
Electronic expansion valve
lead wire
Reversing solenoid
valve lead wire
(Heat pump type only)
Compressor lead wire
Reactor lead wire
Multimeter
(DC voltage range)
(R5222)
Tester's negative terminal
Power transistor
(+)
UVW
Power transistor
(–)
UVW
Tester's positive terminal UVW
Power transistor
(+)
UVW
Power transistor
(–)
Normal resistance Several k

to several M

Abnormal resistance 0 or

(R9747)
W V U