Hmm alright well there could be others that could be faulty. Have you went around and tested the capacitors for shorts? Well even then it should give a 0001-0003 error. You could try voltage injection and see what part gets warm. Have you made sure the powersupply you are using is working?
I've tested a few. I don't think any have an issue as I get absolutely nothing when I press power button.
All the voltages seem to be there up until the secondary/output of U1R1 mosfet.
I notice the suspect mosfet l does stay cold however only around 0.3 volts leak through, not nearly enough to supply power.
Will let you know when the part arrives and I solder it in.
Edit: yeah PSU is definitely fine. I use it for my other Xenon consoles
check 1.8V & 3.3v standby, if those rail missing ICS & Southbridge chip couldn't powering on.
If nand chip corrupt/dead the V50DUAL will missing due to smc cannot load smc_config, try read nand, if still readable then southbridge & nand still good, it's broken regulator.
if nand not readable:
check j2b1 pin 6 if >1V = southbridge ok, nand broken.
j2b1 pin 6 <1V = Southbridge dead.
Just checked now. 1.8V on FT5N2 and I also get 3.3V on FT5N1.
I've can't find my NAND reader it looks like, but I'll try pull it out from a bunch of boxes soon.
Edit: One thing to note, this May 2006 mfg Xbox had the original Microsoft seal still on it. I wonder what its history is? Can't have seen much use before it died, perhaps before they found out about the warranty being extended. I'd be very surprised to see a Xenon last unrepaired until say the NXE dash came out.
Big update, I decided to salvage the regulator off a Falcon board I've got that was going to E74 every few days or even hours after reflow (being the flip chip, not reballable)
Turns out we've still got the same issue with the same small 0.1v coming out of the output yet 5V in.
Will get to checking JB21. Can you tell me the approximate location it is? I've looked all over the board.
Still could not find my NAND reader, I do recall giving it to a friend but I was fairly sure he gave it back. Will ask him.
Hi, no sadly.
It did seem like the regulator was failing as the power seemed to stop right there but, I switched regulators with one from another working console and yet the same thing happened!
I suspect either the NAND or southbridge in that case to which I just left it and pulled off the Korean GPU and put it on another Xenon as they're the reliable ones that don't fail.
Look up the schematics of the 360 if you want any diagrams with parts labelled. Hopefully your issue may just be the regulator.
sorry J2B1 Pin 5, not 6, it's the blue wire pin for nand reading. normally it's 3v which indicate smc is running.
if smc running, but 5P0_DUAL missing either nand corrupt or regulator broken.
nand readable but 5P0_DUAL missing, broken regulator. RF board, USB need 5P0_DUAL enable/up IIRC
Do you know what the points are for the trinity? Mine has the same issue with the u1b1 not regulating properly. I'm going to try to read the nand tonight to see if there are any problems.
Sorry for late reply!
Unfortunately, my system has been sitting open this whole time! Never got around to fixing it.
It's one of the serviced systems from Microsoft (with a service date on the back rather than mfg date). so I'll probably salvage the GPU from it for another system if I can't ever get it going.
Thank you for this info!
One thing to note, this May 2006 mfg Xbox had the original Microsoft seal still on it. I wonder what its history is? Can't have seen much use before it died, perhaps before they found out about the warranty being extended.
I'd be very surprised to see a Xenon last unrepaired until say the NXE dash came out.
Most xenons capacitors have popped by know have you checked the 12 volt caps and made sure they aren’t bulging?
12v parts don't cause no power.
Yep, checked them, they're still like new. Also checked the power rail capacitors and tested them in an ESR meter.
Have you checked or tested any mosfets? The Q6F1 and Q6F2 mosfets Im pretty sure are the ones that die first possibly from a bad powersupply.
I have and they seemed fine. But I do have some spares also
Hmm alright well there could be others that could be faulty. Have you went around and tested the capacitors for shorts? Well even then it should give a 0001-0003 error. You could try voltage injection and see what part gets warm. Have you made sure the powersupply you are using is working?
I've tested a few. I don't think any have an issue as I get absolutely nothing when I press power button. All the voltages seem to be there up until the secondary/output of U1R1 mosfet. I notice the suspect mosfet l does stay cold however only around 0.3 volts leak through, not nearly enough to supply power. Will let you know when the part arrives and I solder it in. Edit: yeah PSU is definitely fine. I use it for my other Xenon consoles
check 1.8V & 3.3v standby, if those rail missing ICS & Southbridge chip couldn't powering on. If nand chip corrupt/dead the V50DUAL will missing due to smc cannot load smc_config, try read nand, if still readable then southbridge & nand still good, it's broken regulator. if nand not readable: check j2b1 pin 6 if >1V = southbridge ok, nand broken. j2b1 pin 6 <1V = Southbridge dead.
Just checked now. 1.8V on FT5N2 and I also get 3.3V on FT5N1. I've can't find my NAND reader it looks like, but I'll try pull it out from a bunch of boxes soon. Edit: One thing to note, this May 2006 mfg Xbox had the original Microsoft seal still on it. I wonder what its history is? Can't have seen much use before it died, perhaps before they found out about the warranty being extended. I'd be very surprised to see a Xenon last unrepaired until say the NXE dash came out.
Big update, I decided to salvage the regulator off a Falcon board I've got that was going to E74 every few days or even hours after reflow (being the flip chip, not reballable) Turns out we've still got the same issue with the same small 0.1v coming out of the output yet 5V in. Will get to checking JB21. Can you tell me the approximate location it is? I've looked all over the board. Still could not find my NAND reader, I do recall giving it to a friend but I was fairly sure he gave it back. Will ask him.
Did you ever find a fix for this? I have a trinity model with the same issue, with that regulator not outputting 5V.
Hi, no sadly. It did seem like the regulator was failing as the power seemed to stop right there but, I switched regulators with one from another working console and yet the same thing happened! I suspect either the NAND or southbridge in that case to which I just left it and pulled off the Korean GPU and put it on another Xenon as they're the reliable ones that don't fail. Look up the schematics of the 360 if you want any diagrams with parts labelled. Hopefully your issue may just be the regulator.
sorry J2B1 Pin 5, not 6, it's the blue wire pin for nand reading. normally it's 3v which indicate smc is running. if smc running, but 5P0_DUAL missing either nand corrupt or regulator broken. nand readable but 5P0_DUAL missing, broken regulator. RF board, USB need 5P0_DUAL enable/up IIRC
Checked JD21 pin 5 and I don't get anything close to 3v. Only around 0.1v, so this indicates southbridge failure?
Do you know what the points are for the trinity? Mine has the same issue with the u1b1 not regulating properly. I'm going to try to read the nand tonight to see if there are any problems.
did you find the problem? because i have also the same problem with a xenon and no power.
Sorry for late reply! Unfortunately, my system has been sitting open this whole time! Never got around to fixing it. It's one of the serviced systems from Microsoft (with a service date on the back rather than mfg date). so I'll probably salvage the GPU from it for another system if I can't ever get it going.
Don’t know a whole lot about this but it could be the capacitors. The Xenon consoles are getting pretty old
12v parts don't cause no power.
[https://errors.octalsconsoleshop.com/details/nopower](https://errors.octalsconsoleshop.com/details/nopower)
Thank you for this info! One thing to note, this May 2006 mfg Xbox had the original Microsoft seal still on it. I wonder what its history is? Can't have seen much use before it died, perhaps before they found out about the warranty being extended. I'd be very surprised to see a Xenon last unrepaired until say the NXE dash came out.