Samsung AC052MNCDKH Service Manual

4-22 Samsung Electronics4-4-8 Communication error after finishing tracking (E202)1. Check items1) Is the communication cable short/open?2) Is there a response from the indoor unit PCB?2. Check procedureNoYesIs there a response from the indoor unit PCB? NoYesIn this case, is thevoltage waveform between the lines squarewave with amplitude over ±0.7V as shownin the following picture?+0.7V-0.7VGoodBadCheck the communication cable andexchange the indoor unit PCB?Remove the communication cableconnecting the outdoor unit to indoor unit,and measure the signal on LINE 2 of theoutdoor unit with a scopeReconnect the cable connectingthe outdoor unit to the indoor unitand restart the unit.If the communication still doesn’t work,ehtecalper indoor unit PCB andCheck the communicationcable in each PCBand replace the PCBYesIs the power/communicationcable connected correctly?No Connect the power/communicationcable correctly.outdoor unit PCB in order of mention.cf.) If there is no oscillo scope, it can be replaced multimeter instead of osillo scope.