NES grey screen

[SlowCoder]

I'm finally getting back to cleaning the pile of "new" old consoles I've collected over the past few months.

 

This weekend I pulled out a dirty ol' NES that needed some love. Got it all cleaned up, pulled the 72 pin connector and cleaned it up. Put it back in and the console would play some games, but not others. Pulled the connector back out again for more cleaning, reinstalled, and all I get now is the NES grey screen for all games I put in. Not even the blinking red light.

 

First thought is maybe I did something to the connector. I put the connector into another console and it works perfectly. Put a known working connector into the troubled console, and still the same grey screen. Not even hitting Reset does anything. So it's not the connector.

 

So I think something may have happened to the mainboard while I was working on it. I don't see any of the exposed components or traces that appear broken, and the console was working sporadically at first, so I think maybe it was just its time.

 

Anything I can check?

[icemanxp300]

I would suggest clipping the lockout pin on the board. That pin causes so many problems it's not even funny. It's a bit tight behind 2 capacitors but w/ a very tiny screwdriver prying out from the left side and finishing on the right side it pops it out quite easy.

[SlowCoder]

I thought the 10NES mod didn't have anything to do with the grey screen? But I have considered trying this if other options fail.

[icemanxp300]

A few months back I had I think 10 systems apart on my floor. I had 2 in particular that were all wacky. One did the same thing you are referring to. I disabled the lockout and it started working. However the vid seems a bit dark in that one I think but it does work. Thats one I'd prolly sell on the cheap though.

 

Since then I have actually removed the lockout in every one because they plain and simply work better. You pretty much eliminate the flashing and games load much much better. I recommend removing the chip regardless.

[SlowCoder]

No go on the 10NES mod. Didn't change a thing. Other ideas?

[icemanxp300]

deoxit the entire board lol. Idk man, in all seriousness deoxit has done some strange things for me.

 

You should check all the conections. It's posssible a wire is lose on one of those connectors.I had a system wouldnt work for nothing. I thew it in a pile and a few months later took it apart again and magically it worked. I think I had a pinched wire somwhere.

[SlowCoder]

The board is in a different case now, so the wire idea is out. I already tried a different PS, re-cleaned the contacts and checked all the components visually for any solder cracks. Since it seemed to be sporadic from the beginning, I'm kind of thinking it is an actual failing part that finally failed. I think I'm going to shelf this unit for a while and wait until I have another nonworking one and see if I can swap parts for better luck.