Detailed Troubleshooting - JBL Balboa SUB10 Service Manual

BALBOA series SUB10
AMP no signal out
Dc voltage check ±Vcc
Check+/-15VDC
Led light green or red
LED light green
Check U202 pin14 signal
yes
Check limiter board C304
yes
Test R121,R122 signal
Check RY101,D102,Q113,Q114 etc
Check U101,Q115,Q116,R138 etc
Check P102 signal
BALBOA SUB10 (UL) AMP
Troubleshooting Flow Chart
no
yes
yes no
Check Q117,118,119,D109 etc
yes
LED red
Check,Q206,Q207,U203 etc
yes
Check U201
no
pin14 signal
yes
no
yes
Check ,+VCC& -VCC
no
DC voltage
yes
Check Q107,Q108,Q105,
Q106,Q103,Q104,U101,etc
yes
no
yes
yes
The Amp ass'Y OK, END
Check Fuse,Transformer,
D110, etc
yes
yes
yes
CheckU201,U202,VR201
VR202. etc
no
Check U301,R343,R344 ,
C340,Q301,Q302, etc
yes
Check J123,J124 etc
no
yes
Set R138 to R140'S
Voltage is 0.51VDC
12