Riddled TV Repair Forum
Service Menu and Manual Schematics
 
   
 FAQFAQ   SearchSearch   RegisterRegister 
   Log inLog in 
Sharp lc-42D62U - Mainboard faulty. Is PSU faulty too?    
Post new topic   Reply to topic    Riddled TV Repair Forum Index -> TV Repair
 
Author Message
tommoose13



Joined: 28 Feb 2016
Posts: 4
Location: Manitoba, Canada

PostPosted: Mon Mar 28, 2016 2:53 pm    Post subject: Sharp lc-42D62U - Mainboard faulty. Is PSU faulty too? Reply with quote

So I'm trying to repair a Sharp Aquos 42" (lc-42D62U)

I have identified the source of my problem as being the mainboard. I ordered a replacement and it came faulty as well, but even less functional than my current mainboard.
With current mainboard, the tv has flickery pixels, but with the replacement it would just go to a white screen then into emergency power-lock state. (I tried a few hard resets/to get into a recovery mode, but to no avail) Put the original board back in, just flickery pixels. (Images in link below)
The seller never claimed that it was tested working, and I have been refunded for the faulty replacement. I am ordering another one, but I am wondering... Is my power supply possibly damaged and did it kill that board? Or would it probably be fine since it works with the current one? I'd really like to avoid ordering the power supply too, as it's not cheap and I've already sunk a little bit of money into this project. :|

Any thoughts or opinions on the matter would be greatly appreciated! :)

http://postimg.org/gallery/kev6zi2g/
Google

PostPost subject: Advertisement

kuhurdler



Joined: 28 Dec 2006
Posts: 2834
Location: Overland Park, KS

PostPosted: Tue Mar 29, 2016 7:14 am    Post subject: Reply with quote

have you measure the power from your power supply? If so, are they close to what they are supposed to be?
tommoose13



Joined: 28 Feb 2016
Posts: 4
Location: Manitoba, Canada

PostPosted: Tue Mar 29, 2016 12:42 pm    Post subject: Reply with quote

I haven't tested the power supply, and my power supply board is labelled very poorly. there isn't anything labelled for voltages as far as I can see. Mind you, I'm no expert in testing TV power supplies, only computer PSUs Confused
kuhurdler



Joined: 28 Dec 2006
Posts: 2834
Location: Overland Park, KS

PostPosted: Tue Mar 29, 2016 2:11 pm    Post subject: Reply with quote

my vote is for a new mainboard. I can't find anything on what values the power supply are supposed to output.

I have seen several of these that you can fix by simply reheating the chips on the mainboard. you would need a hot air gun to do that.
tommoose13



Joined: 28 Feb 2016
Posts: 4
Location: Manitoba, Canada

PostPosted: Thu Mar 31, 2016 11:20 am    Post subject: Reply with quote

Awesome! Thanks for the advice Smile
Google

PostPost subject: Advertisement

manmike



Joined: 29 Jan 2015
Posts: 4
Location: USA

PostPosted: Thu Apr 28, 2016 8:23 pm    Post subject: Reply with quote

This issue is deferentially a defective main board (Video processor IC). Because your pictures the power supply is fine. Look for a replacement main board. Check your main board part number for proper compatibility.
Display posts from previous:   
Post new topic   Reply to topic    Riddled TV Repair Forum Index -> TV Repair All times are GMT - 6 Hours
Page 1 of 1

 


Disclaimer: All information provided by RiddledTV is strictly for information purposes only. Please observe all warnings displayed on your electronic
devices. This information should only be used to help diagnose work, and all service should be performed by a qualified technician.
Contact Us       Privacy Policy       Copyright © 2015 RiddledTV.com       Advertise on RiddedTV.com