Philips HTL4111B/12 Service Manual page 28

OPT does not work
OPT does not work
Check
have the signal
Check U11 P17 whether
have signal On Main PCB
Change the Main PCB
yes
Coax Connector
yes
yes
5-10
no
Check Coax source
no
Check the C53 whether normal or
not
Trouble shooting Chart