JBL Balboa SUB10 - Manual (Page 13)

BALBOA SUB10 (UL) AMP
Troubleshooting Flow Chart
no
yes
yes
yes no
yes
yes
LED red
LED light green yes yes
no
yes yes no
no
yes
yes yes
no
no
yes yes
yes
no
yes
yes
AMP no signal out
Dc voltage check ±Vcc
Check+/-15VDC
Led light green or red
Check Fuse,Transformer,
D110, etc
Check RY101,D102,Q113,Q114 etc
Check Q107,Q108,Q105,
Q106,Q103,Q104,U101,etc
Check ,+VCC& -VCC
DC voltage
Check U101,Q115,Q116,R138 etc
Check Q117,118,119,D109 etc
Check,Q206,Q207,U203 etc
Check U202 pin14 signal
Check U201
pin14 signal
Test R121,R122 signal
Check P102 signal The Amp ass’Y OK, END
CheckU201,U202,VR201
VR202. etc
Check J123,J124 etc
Check limiter board C304
Check U301,R343,R344 ,
C340,Q301,Q302, etc
Set R138 to R140’S
Voltage is 0.51VDC
BALBOA series SUB10
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