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[Snigel]

I jtagged my falcon with XBRv3a, ran it for an hour or two, shut it down. A couple of hours later it just stands there starting itself up, shutting down and keep doing so.

After some help I tried exchanging the diodes, with new ones and the console worked fine again. Tried playing for two hours and now it's back to the "shut down, turn it self on" cycle again.

Since I'm using the recommended 1N4148 I'm thinking they may not be adequate for the Falcon board. Perhaps it's more than 0.75A passing through. The problem is that as soon as the diodes are tougher they are also slower.

So, how fast does the diodes have to be, and is it possible to use a resistor in series with them? If so, any hint on what values that could be good?

[lithium210]

QUOTE(Snigel @ Jan 15 2010, 08:33 PM)

I jtagged my falcon with XBRv3a, ran it for an hour or two, shut it down. A couple of hours later it just stands there starting itself up, shutting down and keep doing so.

After some help I tried exchanging the diodes, with new ones and the console worked fine again. Tried playing for two hours and now it's back to the "shut down, turn it self on" cycle again.

Since I'm using the recommended 1N4148 I'm thinking they may not be adequate for the Falcon board. Perhaps it's more than 0.75A passing through. The problem is that as soon as the diodes are tougher they are also slower.

So, how fast does the diodes have to be, and is it possible to use a resistor in series with them? If so, any hint on what values that could be good?

weird, ive had my falcon for 2 weeks now and havent had any problems with the diodes. Its an ntsc console with xbreboot 3a. I did add a 330ohm resistor between points J2D2.4 and J2D2.7 because i was getting random rare rrod errors but that fixed my problem so far.

[Snigel]

I actually tried putting a 100ohm resistor there the first time the console stopped working. Didn't change a thing. Replaced the diodes and again it was working.

Of course I could try putting a 330ohm there, but the problem seem to be something else.

[lithium210]

QUOTE(Snigel @ Jan 15 2010, 09:14 PM)

I actually tried putting a 100ohm resistor there the first time the console stopped working. Didn't change a thing. Replaced the diodes and again it was working.

Of course I could try putting a 330ohm there, but the problem seem to be something else.

maybe bad solder points? diode black line directed towards the board?  Should have a total of 2 diodes right? But i didnt have the 330ohm before and i havent encountered the issues you're seeing. very strange..

btw.. how do you have the diodes connected besides the black line. Do you have wire->diode->wire or have the diode directly on the board? (btw this is the way i have it)

[Snigel]

QUOTE(lithium210 @ Jan 16 2010, 06:33 AM)

maybe bad solder points?

No, I really don't think so. A pro is helping me out. We tried to re-solder  the old diodes before exchanging them with new ones. Old diodes = no go. New diodes = works like a charm for ~1 hour.

QUOTE(lithium210 @ Jan 16 2010, 06:33 AM)

diode black line directed towards the board?

Yes. Exactly as in this picture: http://pictures.xbox.....s-jasper).png

QUOTE(lithium210 @ Jan 16 2010, 06:33 AM)

Should have a total of 2 diodes right?

Yes.

QUOTE(lithium210 @ Jan 16 2010, 06:33 AM)

btw.. how do you have the diodes connected besides the black line. Do you have wire->diode->wire or have the diode directly on the board? (btw this is the way i have it)

I actually changed this when I changed diodes. So I've tried both ways, it doesn't seem to matter.

[lithium210]

wow.. you got me. possibility of a faulty motherboard? I guess the only testing i would do is remove everything and flash original nand and see how it responds for a day or two. I have no idea what could be wrong here.  Not sure if a bad xbr flash would cause the symptoms you mentioned.

This post has been edited by lithium210: Jan 16 2010, 07:13 AM

[TBAYJ]

2 falcons i did required a 330 ohm resistor @ jd2.4 to jd2.7 instead of a wire ,

[Snigel]

QUOTE(lithium210 @ Jan 16 2010, 07:10 AM)

wow.. you got me. possibility of a faulty motherboard? I guess the only testing i would do is remove everything and flash original nand and see how it responds for a day or two. I have no idea what could be wrong here.  Not sure if a bad xbr flash would cause the symptoms you mentioned.

Thanks for your help anyway! I really doubt that the flash is bad. After I got problems the first time I tried reflashing the board with both XBR and original bios without any luck. Then I removed the diodes, original booted up fine. Soldered new ones, flashed XBR and everything was working (for two hours).
My motherboard could of course be faulty, but it's not a new box I have been using this machine regularly for two years without any single problem.

@TBAYJ: Did you have any of my symptoms before soldering that resistor? First time it started to go crazy I tried soldering a 100ohm resistor there. It didn't change a thing. As soon as I changed the diodes it started working again.

[craz3d]

Are you using parts from the same vendor, purchased in the same package?  Just an FYI, radioshack's electric components are the rejects from vendors with more strict tolerances.  In other words, if manufacturer A makes diodes for reseller B, reseller B mandates that the diodes performance must fall within a certain range.  If a batch of diodes fails to meet those requirements, reseller B will not accept them, instead they go to RadioShack to be sold for a lower price.

Now, you might not have purchased them from RadioShack, but perhaps a similar store.  If you are using diodes from the same box, you could just have a bad batch.  I doubt their packaging lists lot numbers, and I personally used parts from RadioShack w/o problems.  However, there are likely 1000s of people who have performed this modification, and you seem to be the only one whose diodes are 'wearing out' so it might be worthwhile picking up a different set of diodes or the proposed BAT41 diode.

It's either this, you've done something wrong, or there's something wrong with your XBOX.

And in regards to your first post, I find it very unlikely that 750mA or more are pumping through those points.  .75A is a shitload of current to be passing through this part of the board.  The people that devised this hack are fairly competent and knowledgeable people, I doubt they'd make a mistake like specifying the incorrect parts after reverse engineering a state-of-the-art game console.

This post has been edited by craz3d: Jan 16 2010, 11:24 PM

[Snigel]

QUOTE(craz3d @ Jan 16 2010, 11:20 PM)

Are you using parts from the same vendor, purchased in the same package?  Just an FYI, radioshack's electric components are the rejects from vendors with more strict tolerances.  In other words, if manufacturer A makes diodes for reseller B, reseller B mandates that the diodes performance must fall within a certain range.  If a batch of diodes fails to meet those requirements, reseller B will not accept them, instead they go to RadioShack to be sold for a lower price.

Yes they are all from the same batch, so I've also been thinking if they all are bad. I'm from Sweden, so no radioshack. The company is called elfa and is big here. Not known for bad quality afaik.

QUOTE(craz3d @ Jan 16 2010, 11:20 PM)

And in regards to your first post, I find it very unlikely that 750mA or more are pumping through those points.  .75A is a shitload of current to be passing through this part of the board.  The people that devised this hack are fairly competent and knowledgeable people, I doubt they'd make a mistake like specifying the incorrect parts after reverse engineering a state-of-the-art game console.

Yes, I also think that they shouldn't die, still I wanted to try that as a solution, tougher diodes or some kind of protection in the form of resistors. I got some info regarding the current over at xboxhacker, it should be around 1.2mA, so 750mA should really be enough.

[Snigel]

Wanted to post a little update.

I left the machine unplugged over the weekend, when I came back and connected it again, it worked.
Ran games for several hours and left it on standby during the night, not a single issue.
After a couple of days now it has booted up by itself once or twice. Can't really figure out why it does that. If it makes any difference I have a wireless controller connected with the charging cord when this happened.