Mitsubishi Heavy Industries SRK20ZIX-S Service Manual page 87

(C) Power transistor inspection procedure
[Use a tester with a needle indicator for the inspection. (Do not use a digital tester. Check in the AC 300 volt range.)]
(1) If there is a self-diagnosis display, inspect the compressor system (burns, wiring mistakes, etc.) If no problems are found, check the
output of the power transistor.
(2) Output inspection procedure
Disconnect the terminals for the compresseor.
If an output such as the one shown in the figure on the below can be measured, the power transistor and the circuit board for the
outdoor unit are normal.
Output voltage
(ACV)
0
Operation SW ON
(11) How to make sure of remote controller
(1)
Is remote
controller normal?
YES
Again pushing
operating switch
Operating the unit?
NO
Does unit ON/OFF
button operates?
Operating the unit.
NO
Control problem on
main unit
8~10 sec. 1 sec. 3 min.
Measure in this section
Defective remote
NO
controller
YES
Abnormality is not
found.
YES
1 sec. 3 min.
Replace the display.
Is the unit
operable with remote
controller?
NO
Defective remote
controller
Note (1) Check method of remote controller
(a) Press the reset switch of the remote controller.
(b) If all LCD are displayed after one (1) display, it is basically normal.
86
- -
(Example)
RUN light : ON
TIMER light: 2 time flash
1 sec.
YES
Normal