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JVC RX-5V LCD not showing info (just replaced backlight Fuse Lamp)

So now you have the voltage to the tuner PCB, is it working?

I'm not sure why they used MT12ZC in some areas and RD13EB3 in others. One is a 12V zener and the other is 13V. Both are 500mA and should probably be changed to 1000mA. I'm pretty sure the bulbs should be 12V 150mA for your unit. Keep in mind, these zeners don't come into play unless a bulb burns out. That heats them up a shorts them out. This then burns up R875, R876, R877.
 
Thnks for all your replays. I ll buy some 12V bulbs next week, I have on hand only 8V one for my Marantz
After parts replacement receiver starts on tuner mode for first time I got it. This is a good news.
 
I replaced all backlight fuse lamps with 12V ones (not more heat) and all parts for LCD driver local oscillator (330pF caps and 400KHz quartz). No changes, so I belive that LC5813H-246 driver is gone. I bought a JVC FX-330L tuner who has same IC and surprise for me LC5813H-246 driver for LCD display
I also measured voltages on LM7000N pins from PLL circuit on both JVC. On FX-330L I obtain same voltages like in SM specifications. On RX-5V i got:

pin 2 (STRQ) 0,53V - on SM 0V - on FX 0V

pin 3 (CE) 2,18V - on SM 0V - on FX 0V

pin 4 (CLK) 0,02V - on SM 0V - on FX 0V

pin 5 (DATA) 0,03V - on SM 0V - on FX 0V

So problems on pin no 2 and 3. Voltages comes from LC5813H-246 driver
 
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Yes. Is not very hard to do, now I am learning to solder and desolder SMD from old boards. I have Proskit SS-989 station.
Inside FX-330L
20170530_192826_zpsrwyo3qfy.jpg

LC5813H-246 driver. JVC DR-E2BK/LBK use this driver, too.
20170531_184605_zpsgmjrd8r9.jpg
 
On Rx-5V lcd driver is solder on another board in logic section not in tuner board like in FX board. It is important for me that FX board has all parts I need and this for few money (arround 10 euro).
 
I know this is more than 4 years old......
Anyway, I got one of this exact same model RX-5V lately.
The tuner display does not light up, push AM, FM, no response. But I can switch between the others, just not onto tuner portion. The back light seems still working, Did try to find some obvious burnt parts but no luck yet. Did check R862 as @paul_ral mentioned in his but my R862 seems OK.
Any advise on where to start? Thanks.
2nd question: the EQ display on mine seems like one a display to show teh current setting and not "dancing" around along the music, and only one bare for each frequency, is this correct?

I acquired this as my testing or practicing unit but surprisingly the sound quality is pretty nice to me.

IMG_7257[2032].JPG IMG_7262[2028].JPG
 
So the tuner does not work at all, right? Is there power to the tuner PCB? I don't think this model sports a spectrum analyzer. That is a feature of the RX-8V and RX-9V.
 
No, the tuner does not response at all. When I push either AM or FM button, it does not react. I am guessing no power to the display screen nor the tuner board. But I have no idea how to check. Do have the service manual here though.
 
Check the ribbon cables. Look at the schematic and check to make sure the voltages are there and correct. Seems like the tuner board is missing power supply voltage(s).
 
@redk9258 , thanks for your response. so I can check either of the follow locations on the tuner PCB to see there is power or not?
1. Pin 4 on ribbon connector J102 to be 5V
2. leg 20 of IC241 to be 1.3V

I have limited experience and knowledge on this as you can tell by now.

Screenshot 2021-09-09 200133.png Screenshot 2021-09-09 200217.png
 
I also notice the right channel output transistors are running around 114 degree comparing to 100 at the left channel out put transistors. The bias are around 2.0 mV which I just leave them along instead of bringing them up to 3 to 5 mv as suggested on SM. Why there are substantially different running temp? Is this OK?
 
It does show 5.11V and 12.26V, seems like there is power to the tuner board? What will be the next to check? Thanks.

Also pick up several transistors randomly to check their voltages since I don't really know where to trace the issues now,
At Q132, B-1.54, E-0.836 comparing to SM B-1.5, E-0.8, seems OK
At Q133, B-11.24, E-10.8 comparing to SM B-10.7, E-10.0, seems OK

At Q244, Gate-0.27, D-10.30, S-0.50 +/- comparing to SM G-0.6, D-6.5, S-0.7, seems off?
Screenshot 2021-09-10 092943.png
Screenshot 2021-09-10 092908.png
 
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