Samsung CH070EAMC Service Manual page 114

Troubleshooting
12-3-10 When the remote control is not receiving
1 Check if the connector was normally assembled.
2 Put the set in operation and check the voltage of No. 15(+) and No. 16(-) of the main PCB CN91 while operating the remote
control. When the voltage descends below 3V, the assembly module PCB is normal and the main PCB is poor.
Then replace the main PCB.
3 Replace the assembly display PCB because the module PCB is poor if the voltage between No. 15~16 of CN91 maintains 5V
after the remote control starts operation.
12-15 Samsung Electronics