Troubleshooting - JVC MX-G50 Service Manual

Troubleshooting

1. Amplifier
Power malfunction
Front PCB -com
VDD(5V) normal?
UIC1 pin no.18, 46,90
Yes
Front PCB
Does UX1(6MHz)
oscillate?
Yes
Front PCB
When the power is
ON 'H' display at pin
no.15(UIC2)
Yes
Check the main PCB
RIC1(L4959)
No output
AMP PCB AIC1, AIC2
pin no. 4,8,9,12
B+,B- normal?
Yes
AQ 2L, 2R, AQ 1,2,3,4
Emitter B+?
Yes
Is mute selected?
No
Headphone jack short?
No
UIC1( -com)pin79
check the "H"?
Main PCB RIC(L4959)
No
pin no.2, 10 input
voltage normal?
-Check the main PCB
RIC1(L4959)
-Check the front PCB
UD13(L4959)
Front PCB PWR-SENS
No
voltage normal?
(pin no.94;5V)
Yes
Replace -com
No
Replace UIC2(M66010)
Check the B+, B- power source
RBD1, RBD2, RW2
No
Check the power PCB
Fuse, P/T, RFS2, RFS5,
RFS6, RFS7, RFS8
No
Check the AMP PCB
AIC1, AIC2
Yes
Remove it with remocon
Yes
Check headphone jack
soldering condition
Yes
Check the front PCB
UIC( -com), UIC2(M66010gp)
No
Check the AMP PCB
AQ2L, 2R, AQ1,2,3,4
-Check the main PCB;
No
RBD1(PBL403) RD8(IN5392)
-Check the power PCB;
Fuse P/T, RFS2, RFS5, RFS6
-Check the main PCB;
No
RR7, RC7, RZD4, RR6
RR5, RR4, RC8, RD3
MX-G50/MX-G56
1-27