LCD TV has sound and menus but no picture (another philips 37)

[hueman]

Hello everyone,

I have an LCD television that has no picture from cable signal or dvd player.
It DOES have sound and I CAN access the screen's menus.

Originally, I thought that this was likely due to faulty inverter boards (one or both) but since I can use the on-screen menus and see the channel numbers I'm beginning to have doubts. I have opened up the back of the unit. I can see nothing that looks visibly damaged. (no burnt or broken areas and no bulging capacitors)

Can a faulty inverter rob me of my picture but still leave me with menus?
All opinions are appreciated.

This is a Philips LCD Television.
Model: Philips 37PF7320A/37

Thank you.

[tom66]

Re: LCD TV has sound and menus but no picture (another philips 37)

No - the inverters only light up the backlights. If they didn't work, you would get no menu.

Your problem is 100% on the main board. Can't be the T-con, as it doesn't distinguish menus and video.

First I would try an EEPROM reset from the service menu.

To access the service menu: 062596 followed by "I+"

[hueman]

Re: LCD TV has sound and menus but no picture (another philips 37)

I want to thank you for responding to my little post.

I've managed to "fix" my television with the help you tom66's response.
While trying to work around the service menus of my TV, I discovered that the picture did return once I had entered the "Service Default Mode/SDM" and the "Service Alignment Mode/SAM". While thumbing though the menus trying to find some indication of tom's "EEPROM reset", I noticed that the TV's "picture mute" had been switched over to ON. I also discovered that the picture contrast within the TV's custom picture settings had been moved all the way down to zero.

I really have no idea as to why these were adjusted in such a way.
After reading some of my service manual I have to wonder whether this might have had something to do with a corrupted NVM (still don't know what an NVM is really).

Anyway... tom66, your suggestion did help me out of my mess. -Even if it wasn't in the way that you had intended :-)

I was a hair's breadth away from taking the unit to the repair shop... AGAIN.
I have a little one to watch, dinner to make, and had run out of energy/patience.

Thank you.

[tom66]

Re: LCD TV has sound and menus but no picture (another philips 37)

I'm glad you fixed it.

By chance was there a power cut then your TV didn't work after powering back on?

It is somewhat common for the EEPROM to get corrupted - it stores all settings like contrast and presumably also picture mute (which seems like an odd feature to have!) It's normally supposed to remember without power but if there's a power cut and it's being updated at the same time some data can be lost or corrupted.

I have encountered a few TVs that do get the settings corrupted - Samsung and Sharp seem to be quite prone to it.

Anyway, enjoy your TV!

Oh and NVM (Philips term) = EEPROM

[hueman]

Re: LCD TV has sound and menus but no picture (another philips 37)

Well, there was no power cut when it happened.

It did actually happen when I was setting up a Philips branded universal remote. So, I guess it is possible that it was my tinkering that corrupted the settings file. And, this is an embarrassing thing to admit at this point.

This whole event makes we want to take primary course in electronics, just to understand some of the basics. Knowing how to solder well would have come in handy a few times in the past.

thanks.

[tom66]

Re: LCD TV has sound and menus but no picture (another philips 37)

An electronics course won't teach you much about how to diagnose a TV... my electronics diagnosis is always experience and intuition. Like "that doesn't seem right, I better work it out, nope, it is wrong."

Soldering is an excellent skill to have and doesn't take much at all to master. This video will teach you a lot about through hole soldering:
http://www.youtube.com/watch?v=fYz5nIHH0iY

and SMD work (not if you're squeamish - 0.5mm pitch components):
http://www.youtube.com/watch?v=b9FC9fAlfQE

It would be bad design if the IR could cause the settings to become corrupted, but things like that could happen. If it does happen again, you can always reset it through the menu, I suppose.

[bezwiti]

Re: LCD TV has sound and menus but no picture (another philips 37)

Hello,
I just joined and I'm quite happy a site like this exists. I also have a Philips LCD TV model 32pf3321/12 that has sound and no pictures and the problem occurred when a curious visitor fumbled with the remote and probably sent wrong signals to the set(by the way, LCDs are still not within reach of most folks in my country Cameroon central africa). All along, I have suspected the NVM needs reset and after entering the code, got SDM(service default mode) displayed. However, after pressing Menu on the RC, I got language greyed out, and some settings modified. My problem is how to proceed and erase or reset the corrupted NVM(EEPROM). Your help is very much appreciated. P.S. Coincidentally, the remote I was given with the TV which I bought second hand is for model 23pf5321/01

[bezwiti]

Re: LCD TV has sound and menus but no picture (another philips 37)

As a follow up to my previous post(Philips flat screen TV model 32pf3321/12 chassis LC4.31E.AA),when the set is powered up after being disconnected overnight, the screen remains dark, there is sound, the green LED flashes 3 times in quick succession pauses, flashes once, then goes into standby. The red LED does not flash. Meanwhile, it powers on again and the cycle of green LED flashes continues at least 6 times before the screen switches on(faint glow). Now, one can see the channel numbers, the menu, etc. While the images are faint, the full raster is absent on a blank channel and switches directly to a blue background. Next point is when the service code is activated, I get SDM, SAM or CSM(depending on which combination was typed on the remote control) displayed on the far top right corner but no other details. A service manual indicates that I could type the code “062598” directly followed by the “MENU” button and “XXX” (where XXX is the 3 digit display panel option code) in order to force the set to reinitialize the display,but how do I know my display panel code since the label inside the doesn't seem to have any! The production number is HJ100701128273 - made in Poland. Help please...!!

[okmk666]

Re: LCD TV has sound and menus but no picture (another philips 37)

Hi!

I have a brand new 55pfl7108K TV. When sometimes I turn it on I have sound, lights and can move to sources but no pic. After taking the plug off and on from the power it works.

Any idea?