Philips DVD580M Service Manual page 25

Diagnostic Software, Trouble Shooting and Test Instructions
5.3.10 Microphone Not Working
No voice from Microphone
Go
Check point : the Q17 on decoder board
Observe : check the collector terminal voltage is +0v7
No
Check point : Q16 on decoder board
Observe : check if the Collector terminal is short circuit to
ground
No
Check point : pin 1 of U205 on power supply board
Observe : check the +5V is presented
Yes
Check point : Microphone input
Observe : check if the any signal presenting at pin 1 of CN205
by hitting the microphone
No
Check point : VA+ and VA- on Microphone board
Observe : check if the supply voltage is + / -- 9v3
Yes
Solution : replace the U401 on Microphone board
5.3.11 Microphone Cannot Sw Off
Cannot turn OFF the voice from Microphone
Go
Check point : Microphone control key on remote control
Observe : press the key and check the voltage changes on
R114
Yes
Check point : collector terminal of Q17 on decoder board
Observe : check the voltage is 0v7
No
Solution : Replace Q17
Solution : replace the transistor
No
Solution : replace the Q16
Yes
Solution : check the +5V supply
circuit, replace any defected
Yes
components
Solution : Replace U205 on power
supply board (karaoke part) if no
Yes
signal output from pin 15
Solution : check the connector
No between power board and
Microphone board
Figure 5-10
Solution : check if any short circuit at
No
signal link
Solution : check and replace Q16 if
Yes
defected
Figure 5-11
DVD580M 5.
CL 26532085-069.eps
CL 26532085-070.eps
EN 25
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