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#1
06-04-2007, 10:01 AM
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Troubleshooting JVC D-Series
Hi Guys...
I have been an active AK member for some time, but never had much reason to wander around in the TV forums on a regular basis until now. I am hoping that some of the technically inclined folks here might be willing to assist in some troubleshooting, and help me determine whether a repair might be feasible. I have a relatively recent JVC D-Series 27" TV that just quit the other day. It was working fine, and suddenly I heard a soft "click", and the unit went dead. The unit powers on, either manually, or via remote, but there is no sound or video... not even any on-screen menu. Are any of these modern units serviceable? In this case it seems like there is a high probability that it might even be a simple fix... perhaps a fuse or relay? I haven't been brave enough to remove the rear cover and peek inside yet... hoping that the more experienced folks here might offer some guidance. I am relatively competent with a DMM, and have basic soldering skills. Any suggestions? Are there any components inside that I can check and/or replace myself? Thanks in advance.... Henry P.S. The model # is AV-27D302, manufactured in June 2001 Last edited by hpsenicka; 06-04-2007 at 12:45 PM. 
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#2
06-04-2007, 10:38 AM
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An update..
Well my curiosity got the best of me and I decided to pop the cover off and have a peek inside. The fuse on the power supply board is OK, but there is a second fuse on the main circuit board that was burnt. Time to run out and get a couple of replacements and see what happens. I did see some slight discoloration of the main pcb in one area indicating a bit of long-term overheating. There are a couple of diodes and resistors in this vicinity. No obvious visible indication that any of the resistors or other components are burnt, so I am optimistic that it might be as simple as a fuse replacement, although in the back of my mind I am wondering what caused it to blow. Edit: popped in a new fuse... still no love! 
Last edited by hpsenicka; 06-04-2007 at 11:18 AM.
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#3
06-04-2007, 02:38 PM
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It's not a bad idea to start by checking areas that have obviously been hot. The heat damage isn't usually a sign of a problem, but areas that run hot are more likely to fail, or develop bad solder connections.
The first thing I would check is the HOT (horizontal output transistor). This is the large transistor on a heat sink near the flyback (high voltage transformer). If it shorts, it will either blow the fuse, or shut down the power supply. It often fails for no reason, but there are lots of things that can cause it to fail. The problem is probably not serious, but unless you want to spend a lot of time learning about how to repair TVs, it would be better to have a professional look at it.
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#4
06-04-2007, 02:46 PM
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Quote:
The unit belongs to my elderly parents, and after a few moments of reflection I have decided to do just what you have suggested above. Took it to a local electronics repair shop to get a free quote... if they can fix it at a reasonable cost, we will just let them do it. If it proves to be uneconomical to have professionally repaired, I will be back to square one with a unit that I can learn on! In today's market, it can be tough to rationalize an expensive repair when new units are available so inexpensively.... but I hate to send a decent unit to the scrap heap if there is potentially a reasonable repair available.
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#5
06-05-2007, 01:48 PM
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Well, turns out to be not so simple after all.... apparently the Flyback transformer failed, and took out the HOT when it went.
The technician will have it fixed by tomorrow morning. The repair bill is going to run about $150.... more than I had hoped, but not outrageous.
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