2 7
Dolby Pro-Logic
Ò
A/V Receiver
JSR-400
MORE COMPLEX TROUBLESHOOTING
Symptom
Cause and Remedy
Receiver inoperative
A) Faulty AC power cord. (FL indicator does not light) Replace.
B) Defective power switch. Replace.
C) Broken wire in the power transformer. Replace the power transformer.
D) Blown fuse. Replace the fuse.
Fuse blows when power is
A) Defective power transformer. Replace.
turned on.
B) Short on the primary or secondary of the transformer circuitry. Repair the short.
C) Damaged rectifier (D20) or damaged “transistor (Q3, Q11, Q12).”
Replace the defective component(s).
D) Short circuit in the amplifier circuit. Replace the shorted component(s)
in the amplifier circuit.
FL indicator lights but no sound
A) Defect in IC3 on the Main Board. from both channels.
Replace the defective component(s).
One channel does not work when
A) “Defect in IC2,IC3 on the Main Board” signal applied to the center terminal
volume is at maximum with a test
volume is at maximum with a test channel. Locate and correct the defect.
Signal applied to the center
terminal of volume control VR1 of
B) Break in copper foil of printed circuit board. Repair the trace.
The dead channel.
C) Short in speaker output terminal. Repair or replace.
Speaker works normally but
A) Headphone plug does not mate with jack. Replace the jack.
Headphones inoperative.
B) “Defective resistor R52, R53.” Replace.
FM inoperative
A) Defective front-end. (PACK1) Replace.
B) Defective FM switch. Replace the switch.
C) “Defective transistors Q1,Q2,Q3,Q201,” “Q202 or IC2, IC3, IC4"
Replace the defective transistor(s) or IC(s).
D) Defective coil T4. Replace the coil(s).
E) Defective lead-in. Repair or replace the lead-in.
F) “Ceramic filters F101, F102 defective.” Replace the defective ceramic filter(s).
G) Defective controller circuit component. Replace.
Poor multiplex separation
A) Improper adjustment. Readjust VR401.
B) IC4 defective. Replace.
C) Variable resistor VR401 defective. Replace the variable resistor.
STEREO indicator does not light.
A) Defective indicator in FL. Replace.
B) Defective IC4. Replace the defective component.
Summary of Contents for JSR-400
Page 37: ...JSR400 MAIN PCB H G F F G H E D C B A A B C D E I I 1 JSR 400 PAGE 31 1 of 2...
Page 38: ...H G G H J I L M K O O P P L M I J K JSR 400 PAGE 31 2 of 2...
Page 39: ...JSR400 Con H G F F G H E D C B A A B C D E JSR 400 PAGE 32 1 of 2...
Page 40: ...JSR400 Control PCB IC1 H G G H L M K J I L M I J K JSR 400 PAGE 32 2 of 2...
Page 43: ...JSR400 SUB PCBs H G F F G H E D C B A A B C D E I I JSR 400 PAGE 34 1 of 2...
Page 44: ...H G F F G H E E L M K J I L M I J K JSR 400 PAGE 34 2 of 2...
