Subwoofer Amp Troubleshooting - JBL ES250PW Service Manual

ES250PW
Dc voltage check
±Vcc,±15V
Power on check
LED red &green
Test frequency
Response
Test frequency
Response
Test input sensitivity
Downloaded from www.Manualslib.com
ES250PW Testing Flow Chart
Start
no
Check transformer
OK
C C ,D
168, 169
D C
124, 170
yes
Check vol module
no
& connector
OK
cable& ±15V.etc
yes
no
Check U
102
OK
C R ,C
121, 135
yes
no
Check U105
OK
C137C137CC143ect
yes
no
Check U
101
OK
R R etc
112, 114
manuals search engine
Test protection
,
123
Test limiter circuit
Check THD output
power, noise
Auto off Function
,uR ,
133
Hi pot test
.ect
122
Listening test
The Amp ass'y ok
,R
117,
14
yes
no
Check U
OK
±15Vcc etc
yes
no
Check U
OK
yes
Check pre board
no
OK
& power board ,
±Vcc,±15V ect
yes
Check U
no
Q .C
102 131.
OK
cord, Transformer.
yes
no
OK
yes
END
.R
107 237
.Q ect
106 107
.Q
103 101.
R ;AC
142