Xbox Original 1.6b, video out *only* via composite

Hello ASSEMBLERgames,

NeoGAF sent me your way--saying you're the best at this kind of thing. Did a preliminary search here for "Xbox composite" but no related hits: can you help me troubleshoot this?

Let me walk you through my setup:

Functioning Xbox (A) stacked on top of misbehaving Xbox (B).
Known good component cable gives picture for A, not for B.
AV box via composite gives a picture on A and B.
AV box via S-video gives a picture on A, but not B.

What in gods green earth is going on here? Via composite I can navigate unit B but the only video settings over composite are Standard, Letterbox and Widescreen.

I've tried them all, and then swapped back to component but no love.

Is this...a thing? A failure of all video EXCEPT composite? A way it can get "locked" to composite on the software side?

I've tried a Panasonic Plasma, a Vizio LCD, a Sony PVM-2530, and another CRT. Unit A works on all of them. Same cable(s) on Unit B show nothing unless using composite (and I get audio). I've run the both through a DVDO Edge, and A works--B shows "no signal".

Is there a button combo to "reset" the video chip? What else can I try? What should I be looking for?

Thanks for any help you can provide. If you need a picture of anything else, let me know!

Back of motherboard CU pinout

Interior pins top

Interior pins bottom

whole board top

whole board bottom

 

I'm not sure if it would help, but I had to switch my Xbox to NTSC region using this tool:
http://digiex.net/downloads/downloa...o-select-2-xbox-region-switcher-ntsc-pal.html

Since I had PAL XBOX which doesn't support component signal out of the box.

 

It's news to me. Looking around now though, I can say I've seen claims of that (if unsubstantiated).
I just thought you'd be limited to 480i/576i.

 

Pal does but it's 480i ONLY
@HDgaming42
Read this: http://forums.xbox-scene.com/index.php?/topic/749141-component-cable-problem/

Worst case the video encoder has shat the bed, like in the link, check the component outputs to see if they are shorted to ground.

Also have a squizz to see if any components have been knocked off

 

Wow! Spot on! It seems my board is lacking cap С5A5. Can anyone tell me what I'd put there? Never worked with something that looks like that...

 

The encoder for the 1.6 is known to be ehh but it shouldn't be "locked" to composite at all as long as the dash supports higher resolutions and virtually all modern dashes do.

Have you tried the component cable on a second xbox? I don't recall how the XBox detects what cable is plugged in but if it thinks the cable is composite it won't let you set 1080i normally. XBMC might support it but I'm not sure, obviously composite won't do 1080i but it might let you set it...and then lose picture.

 

That looks like it was intentionally left unpopulated by microsoft, meaning it's not the issue.

 

I'm confused. The thread you directed me to--that was literally his solution, to cap C5A5.

I'm struggling to see how it could be a PAL console. It was purchased in Canada (albeit second hand). How would I tell? Google is a mess now with Xbox, Xbox360 and Xbox One results flooding into searches...

 

@LeHaM OK, so I disassembled my working Xbox (also a 1.6b) and it appears it also lacks a cap on C5A5. I guess you're right--it's not necessary for component output.

I'd hoped to avoid wandering into unfamiliar territory and looking foolish, but here it goes: How do I check to see if "component is shorting to ground"? Anyone care to explain it to me?

Is that using a multi-meter in continuity mode? One lead on the motherboard pin, the other on the AV pinout?

I've changed dead, leaking and exploded caps before, but beyond that my electrical experience is pretty low. Go easy on me plz!

 

It's the latest dash; I've used a second Xbox (in the OP) and even a second set of component cables.

The cables are verified good.