Serial (Rs-232) Troubleshooting - LG LRM-519 Service Manual

13. SERIAL (RS-232) TROUBLESHOOTING

Serial (RS-232)
Problem
YES
NO
Serial Cable
Connection OK
YES
NO
IC805(16-pin) +5V
Input OK
YES
NO
J805(11-pin) "TX
Data" Present OK
YES
NO
J805(14-pin) "TX
Data" Present OK
YES
NO
J805(13-pin) "RX"
Present OK
YES
NO
J805(12-pin) "RX
Data" Present OK
YES
Serial (RS-232) OK
Serial Cable
Connect
J900 Connector
Power Cable Check
Check IC302 &
Re-soldering
Check IC805 &
Re-soldering
B805 Re-soldering
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