AU-A129 - Sharp Air Conditioner Service Manual (repair manual). Page 22

22

The room is not cooled.
The compressor does not operate.

Measure resistances of TH1 and TH2.

The control circuit is normal.
   The compressor may be defective.
   The running capacitor may be defective.
   Refrigerant may have leaked.
   The outdoor fan motor may be defective.
   The outdoor fan motor capacitor may be defective.

Push the button "TEST" on the 
indoor unit, and wait 3 minutes.

Is there a  voltage

between terminal "N" and

"1" of the terminal board the

power supply voltage ?

Are the resistances

correct Fig. 1 ?

Replace the thermistor ass'y with a new one.

NO

YES

YES

NO

Replace the PWB ass'y with a new one.

0

20

40

60

80

100

120

140

160

180

0

10

20

30 40˚C

-10

CHARACTERISTIC OF TH1 & TH2

Using a meter, measure voltage at
the terminals on the terminal board.

K

10˚C
30K