Riddled TV Repair Forum
Service Menu and Manual Schematics
 
   
 FAQFAQ   SearchSearch   RegisterRegister 
   Log inLog in 
Sharp 55R-WP4H rear projection TV black and white    
Post new topic   Reply to topic    Riddled TV Repair Forum Index -> TV Repair
 
Author Message
blackrv7



Joined: 30 Dec 2008
Posts: 5
Location: KY

PostPosted: Tue Dec 30, 2008 10:17 am    Post subject: Sharp 55R-WP4H rear projection TV black and white Reply with quote

On initial turn on, my Sharp 55R rear projection tv is in color but switches to black and white after a few minutes. Prior to going BW the picture is HD and all other functions of the TV work fine. I've searched different forums and FAQ but haven't found an answer to the repair. Thoughts? Thanks in advance
Google

PostPost subject: Advertisement

kuhurdler



Joined: 28 Dec 2006
Posts: 2879
Location: Overland Park, KS

PostPosted: Tue Dec 30, 2008 10:29 am    Post subject: Reply with quote

I've never seen a model number like that. Can you check the back and confirm?

I have a 55R-WP4H on record. It says to check for broken circuit traces. There's also a history of bad convergence amps with this model, but that doesn't sound like it's your problem.
blackrv7



Joined: 30 Dec 2008
Posts: 5
Location: KY

PostPosted: Tue Dec 30, 2008 11:08 am    Post subject: Reply with quote

kuhurdler wrote:
I've never seen a model number like that. Can you check the back and confirm?

I have a 55R-WP4H on record. It says to check for broken circuit traces. There's also a history of bad convergence amps with this model, but that doesn't sound like it's your problem.


You are correct, I just didn't put the entire model number in the original post. It is, as you refer, a 55R-WP4H. I call a tech and he said to smack the TV on the base to see if there was a loose connection somewhere....sounded "different" to me but I did and image will go to multiple colors. Believe it or not :o I can smack it and it will sometimes go color but it will not stay but a few minutes. Convergence amps? Geez, that's a bunch of boards to look for traces, can I narrow down my search.

Thanks
blackrv7



Joined: 30 Dec 2008
Posts: 5
Location: KY

PostPosted: Tue Dec 30, 2008 11:37 am    Post subject: Reply with quote

One other bit of information, it "seems" the longer I leave it unplugged, and not just turned off, it will stay color longer than if I just unplug it for 5 minutes or an hour.
kuhurdler



Joined: 28 Dec 2006
Posts: 2879
Location: Overland Park, KS

PostPosted: Tue Dec 30, 2008 12:54 pm    Post subject: Reply with quote

yes, that is likely because your circuit trace problem is temperature related. As the metal heats up, the metal on the circuit board expands.
Google

PostPost subject: Advertisement

blackrv7



Joined: 30 Dec 2008
Posts: 5
Location: KY

PostPosted: Tue Dec 30, 2008 3:34 pm    Post subject: Reply with quote

kuhurdler wrote:
yes, that is likely because your circuit trace problem is temperature related. As the metal heats up, the metal on the circuit board expands.


Thanks for your input but let me pick your brain a little. I can "whack" the side of the TV and make it go from black and white to multi-colored, just whacky looking. If I keep doing this, I can eventually get it to go totally B&W to the point there is a great BW picture...if I want to watch B/W TV. In looking inside, there are two large circuit boards mounted horizontally with a couple more boards behind the RCA cable inputs. If it is a board issue, which it certainly seems is the case with something loose, which board would you think is the one which is controlling the color? I've blown it out with air and looked for anything obvious, but don't see anything.
blackrv7



Joined: 30 Dec 2008
Posts: 5
Location: KY

PostPosted: Tue Dec 30, 2008 4:46 pm    Post subject: Reply with quote

kuhurdler wrote:
yes, that is likely because your circuit trace problem is temperature related. As the metal heats up, the metal on the circuit board expands.


One other thing to consider, with the TV on and looking in the back, anytime I tap the right hand (as looking from behind) horizontal board, or especially the aft most vertical board behind the RCA jacks and get the picture to to display blue and red horizontal lines. Also the heat dispensing alum piece that has a board mounted on top of it is almost hot to he touch to the point to my uneducated brain says it's hot. Should it radiate that much heat? What do you think, unplug it tomorrow and start pulling boards off that right hand side and look for loose circuit board connections or might it me some sort of module going bad?
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.
Privacy Policy       Copyright © 2020 RiddledTV.com       Advertise on RiddedTV.com