JBL JSR-400 - Receiver

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Dolby Pro-Logic
Ò
A/V Receiver JSR-400
Symptom Cause and Remedy
FM volume not sufficient. A) If volume from both L and R channels is not loud enough: Front end section
defective. “Faulty IC3, Coil T4" Defective C412 on Tuner Board. If sound of one
channel is not loud enough: “Defective Q401, Q402"
AM inoperative A) Damaged IC3 of tuner board. Replace.
B) “Defective T1, T2, T6 or F202 of ” Tuner Board. Replace the defective component(s).
C) “Resistors R301, R302 defective.” Replace the defecive component(s).
D) “Capacitors C438, C322, C412 defective.” Replace the defective capacitor(s).
E) Defective AM switch. Replace.
F) “Defective varicap diodes VC1, VC2.” Replace varicap diode(s).
G) Damaged AM loop antenna. Repair or replace.
H) Defective controller circuit component. Replace.
Bass control has no effect. A) Variable resistor BASS defective. Replace.
B) “Defective R60, R63, C47, C48, C52, C53" Replace the defective component(s).
Treble control has no effect. A) Variable resistor TREBLE defective. Replace
B) “Defective R70, R73, R77, R79, ” “C58, C61, C63, C64.”
Replace the defective component(s).
Auto tune inoperative. A) Poor contact on Up/Down key. Repair or replace.
(UP/DOWN)
B) Defective IC on Front Board. Replace.
C) Defective tuner circuit components. Replace.
D) “In case of FM only, improper adjustment” of FM front-end. Readjust.
Manual tune inoperative. A) Poor contact in Up/Down key. (AM or FM) Replace.
(UP/DOWN)
B) Defective IC1 on Front Board. Replace.
Memory setting (Keys 1-10) A) Poor contact on memory keys 1-10. Replace
inoperative.
B) Poor contact on memory set key. Replace.
C) Defective IC1 on Front Board. Replace the defective component.
FL inoperative. A) FL defective. Replace.
B) Defective IC1 on Front Board. Replace.
Noisy volume control. A) Defective volume control. Replace.
B) “Defective capacitors C1, C2.” Replace the defective capacitor(s).
Remote Control Unit inoperative. A) Weak battery. Replace.
B) Defective. Replace.
C) Defective IC1 on Front Board. Replace.