Daikin FTXS09HVJU, Service Manual

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SiUS04-904 Check
150 Service Diagnosis
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 you cannot avoid to touch a live part, make sure that the power transistor's supply voltage is
below 50 V using the tester.

For the UVW, make measurements at the terminal on the PCB or the relay connector.
5.1.12 Main Circuit Electrolytic Capacitor Check
Check No.15

Checking the main circuit electrolytic capacitor

Never touch any live parts for at least 10 minutes after turning off the circuit breaker.

If you cannot avoid touching a live part, make sure that there is no DC voltage using the tester.

Check the continuity with the tester. Reverse the pins and make sure there is continuity.
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

malfunctions