Check
SiBE041025
90
Service Diagnosis
5.1.8 Power Module Check
Check No.13
Note:
Check to make sure that the voltage between (+) and (–) of the diode bridge (DB1) is approx.
0 V before checking.
Disconnect the compressor harness connector from the outdoor unit PCB. To disengage the
connector, press the protrusion on the connector.
Follow the procedure below to measure resistance between the terminals of the DB1 and
the terminals of the compressor connector with a multi-tester. Evaluate the measurement
results for a judgment.
5.1.9 Indoor Unit PCB Output Check
Check No.18
(1) Check the connector for connection.
(2) Check the motor control voltage is generated (between the pins 2 and 3).
Negative (–) terminal of
tester (positive terminal
(+) for digital tester)
DB1 (+)
UVW
DB1 (–)
UVW
Positive (+) terminal of
tester (negative terminal
(–) for digital tester)
UVW
DB1 (+)
UVW
DB1 (–)
Resistance in OK
several k
Ω
~ several M
Ω
Resistance in NG
0
Ω
or
∞
(R11979)
12
11
10
9
8
7
6
5
4
3
2
1
Phase U
Free pin
S200
Free pin
Free pin
Free pin
Free pin
Free pin
Phase V
Phase W
GND
Motor control voltage (15 VDC)
Rotation pulse (5 VDC)