20 Most Recent JVC AV-56WP74 56" Rear Projection HDTV-Ready Television - Page 8 Questions & Answers

You need to replace the convergence chips which have become duds

It sounds like the cooling fluid in your picture tube(s) has become dicolored - this can be seen if you dismantel the unit and view the picture tubes directly - they will appear foggy - replacing the fluid can be a time consumming and expencive task.

you also need to check and replace low value resistors in that circiut.they are all 1 watt,usually they get discolored when stressed.R842 2.2 ohm,R854 and R846 1.5 ohm,R850 2.2 ohm,R858 3.3 ohm,R862 1.8 ohm.they must be the exact value available in MD from surburban electronics.please note stk392-110 upgrade to stk392-150 for future referance.ONCE AGAIN CHECK ALL LOW VALUE RESISTORS

I don't think I need to pay you so you can tell me that I need to have some one come in and repair this. It sounds like it neds a new relay and I don;t think you can fix this on line.

av56wp74? This is a fairly easy repair if you know how to solder---most of these sets use two convergence chips---I can tell you how to do it--you will need two new chips and maybe a resistor or two--sometimes the chips damage a resistor around them--this set is a easy fix--look in your area for someone who will do it in your home--I do hundreds of them here for 200-250 total--if you want to know what is involved to do it yourself--give me a vote here and I will tell you.


REGARDS, SD TECH

The main power transformer is either going bad or has bad solder points holding it on to the board. sometimes if it is a bad solder joint sound vibration from the speakers can cause the solder joint to disconnect and this inturns trips the system to power down. what make and model of TV?

try running the TV on Mute to see if it is a sound vibration jiggling a loose solder connection.

Yes, flux helps soldering joints and makes it shiny and proper joint.

Your symptoms sounds like a damaged convergence IC.

There are two and large IC’s that control the convergence in a big screen set. They are secured to a very large aluminum heat sink. They will have a part number stamped on them that will start with an STKXXX-XXX, like STK392-110, and they are located on the signal board (on the left as you look into the back of the set).

Along with the convergence IC’s there will also be some associated components that will need to be replaced as well. There are some resistors that are part of the convergence circuit that will be open and need to be replaced. Most likely these will appear charred in the center. If you have an Ohm Meter or a DVM, check all the resistors that are close to the IC’s and you should be looking for either ones that have opened or have changed values.
There are also two resistors on the front of the board located in the middle that are fusible link resistors, these should be checked for opens and replaced if they are found so.

I would suggest that you contact a service center in your area for a complete diagnosis and repair, as this type of repair can get a little tricky. But if you want to repair the set yourself, just remember to be careful. The capacitors and CRT’s can hold a charge and may shock you.


If one of the convergence IC’s are found to be bad, I would replace them both, if one has gone bad the other may go soon. I usually order my parts from Andrews Electronics in California, they will have the OEM components that you will need.
Their site is http://www.andrewselectronics.com/welcome.aspx
And their phone number is a 24-Hour Order Desk: (800) 274-4666
I recommend the phone order so you can talk to the person about the different types of IC’s that are available.

I would also advise that the convergence IC’s be OEM or better, just because they are cheap does not mean that they are a good deal. I have seen the cheap IC’s fail after a short time, even though they look exactly like the OEM IC’s. I think that the bottom line is that you will get what you pay for when it comes to the parts.

You can also try http://www.tvrepairkits.com/ , I have not tried them yet, but they do carry OEM or better parts.

I hope this information allows you to resolve this issue.
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If you need further assistance please comment to this post and I will try to help you further.

The STK392-110 are the stock ICs for your JVC. Chances are one or more of the feed resistors are bad. JVC TVs will usually have at least one bad resistor when the original ICs fail

This is a very common failure on Projection TV sets.
Screen looks 3D
Colors don't line up
One or more colors can't be adjusted when using the convergence menu.
Screen is bowed or warped.
You can see some example photos and find a solution here...
http://www.fixya.com/support/r2861627-updated_convergence_problems_amp

Press the [SLEEP TIMER] key and set the SLEEP TIMER for "0" MIN. While the
SLEEP TIMER information is still on screen, press the [DISPLAY] key and [VIDEO
STATUS] key of the remote control unit at the same time to enter the SERVICE
MENU.

Exit the service menu by twice pressing the [EXIT] key on the remote.

Please rate our help to keep the free service online

hit sleep timer while that is still displayed at 0 hit display and v.status on your remote (make sure the switches on the remote are set to tv and the other switch is set to vcr) that will get you service mode

you have some resistor open off of the ics that you replace like 1.8 ohm 1watt or 2.2 ohm or 2.7ohm

yes its the convergence board. you can try to adjust this from the tools menu, but it unlikely you will get much improvement The board needs replacing

AV56wp74? The power button blinking blue means the set is in shutdown----the most common reason for this in this set is one of the two convergence chips is shorted. The way I usually prove this is to remove rear cover and or front grill and examine convergence circuit located at the front of the set----Also--I will unplug the plug from that circuit board that goes to the TV's power supply---if the set turns on with the convergence circuit board unplugged from it---you know your trouble is one of the two chips---if this is the case both have to be replaced and the set adjusted.


I do this here for free so if this has helped you give me a vote here. If you have questions or need help let me know.

la fuente de alimentaciom y vulve a revisar minuciosamente le convergencia poedes tener una resistencia elterada o abierta

Your TV most likely has a convergence failure. ( common problem )

Here are some of the most common symptoms and example photos of a convergence problem

• Screen looks 3D
• Colors don't line up
• One or more colors can't be adjusted when using the convergence menu.
• Screen is bowed or warped.

Here are some photos of convergence problems.




Here is a quick test....

Using your original remote go-to the tv settings then goto the convergence section.

Try to adjust the red and then the blue convergence.

You should be able to move them up, down, left, and right.

If you can't move them in all directions your convergence chips are bad and should be replaced. This is a common problem.

SOLUTION

You will need to replace the convergence chips and possibly some convergence resistors and pico fuses. Its a fairly easy DIY job or you can call in a pro. If you want to do the repair yourself check the site www.TvRepairKits.com. Their kits include a photo instruction guide, original OEM Sanyo STK chips, convergence resistors, pico fuses, thermal paste, email/phone support, etc.

Throw it out of the window

this set(AV56wp74) was first made in 2003----if you use the remote for the set and go into the customer menu---select convergence----once there see if the red and blue will move left/right and up/down----if either color will not move in any one of these directions----you have a bad convergence IC--this set uses 2 of the STK-392-110 output ic chips---both need to be replaced and the set adjusted with the original JVC remote control. I hope this has been helpful.

You need to replace the power supply board. The new ones have a bigger heat sink - obviously JVC knows about the problem because they made the new ones bigger. It cost $250 from JVC and I installed it myself - took about 3 hours to do. If you are not tech savvy call a repairman. Hope this helps.