SG 2020 - JBL Audio Service Manual (repair manual). Page 11

Read JBL SG 2020 Service Manual online

-11-
A
NO
NO
NO
NO
NO
NO
Laser does not light.
Is “3.5V” applied to pin      of IC 801?
Is power supplied to laser Q801?
(Q 801 collector: about 1.8V)
Does laser current flow?
1.0V across R801
Is data transferred from
MICOM IC ?
Does voltage appear at IC
803 pin 
?
Defective MICOM.
Defective MICOM.
Defective connector.
Defective IC 801, 803 
Defective slide motor and/or
connector.
Defective LMT SW and/or
connector.
Defective Q 801 and/or laser.
Defective laser and/or
connector.
Did pickup return to
innermost circular?
Does it stop at inner pick
circular after shift?
Is defect output from LM
SW applied to pin 
of
PN803?
R801
1.0V
R801
1.0V
YES
YES
YES
YES
OPEN
CLOSE
YES
YES
YES
YES
YES
YES
70
11
12
2
Page of 73
Display

Click on the first or last page to see other SG 2020 service manuals if exist.