Falcon JTAG died one day

[sm0k4 187]

I came across a Falcon box that was able to be JTAGd. I modded it and everything was running good until a day after I updated to 14719 dashboard.

It was running after I upgraded the dash, but the next day when I went to turn it on it was completely dead. No RoL or nothing. Like it wasn't getting the Power ON signal.

I tested the FETs, they are fine. No shorts anywhere either and the PSU light stays Amber.

Anything else I can look into? I might try to reflow the SB IC, but if anyone has seen this, any help would be appreciated.

Thanks.

 

[dantun]

May sound like I'm stating the obvious but have you tried a new powerpack?

 

[Beejeex]

i had the same thing with a jtag falcon.

i reflashed it to the previous version then everything worked fine again.

in the end i made an image for 14719 with xebuild with minimal dashlaunch settings and the right smc that worked for me before.

Bee

 

[sm0k4 187]

Sorry, I should have stated I tried 3 diff power packs and all 3 work with a good xbox. I'm an elec. test engineer so I know my way around. I just don't know what parts of the mobo control the power on signal. I hear the ANA and SB does, so maybe I will give that a go.

I also tried my old NAND that worked with 14717 to no avail. I'm beginning to think something is goofy with the hardware, and from research it could literally be anything. I will have to go over the board with a fine tooth comb and look for anything amiss. Too bad there isn't a schematic.

Thanks for the replies.

 

[Mister_X]

Could be a corrupt SMC. if its damaged or blank the box will not do anything.

 

[sm0k4 187]

Wouldn't it not boot from the start after flashing 14719 if the SMC was bad/corrupt? I wasn't aware of it all of a sudden becoming corrupt after flashing if it works at first.

 

[Martin C]

Wouldn't it not boot from the start after flashing 14719 if the SMC was bad/corrupt? I wasn't aware of it all of a sudden becoming corrupt after flashing if it works at first.

Depends - after updating the console, did you unplug it from the mains for at least 20 seconds? You need to do this to clear the SMC cache in the southbridge.

If you didn't, the only time you'd have a problem is when you actually did power it off from the mains completely. Otherwise it just holds onto the previous SMC and you're none the wiser.

 

[sm0k4 187]

Well, the thing is, after 14719 update I had FSD running to test temps out after new thermal paste. Then I unplugged it and let it sit idle and unplugged for a day or two. When I went to boot it up again it was completely dead. I did see a piece of solder on the board but that wasn't the problem.

I went over the whole board carefully and noticed no other bridges. I get all voltages to come up on the FETs and no shorts between power rails.

This is an odd issue since I would expect there to be a short or power issue somewhere. All usb sockets are fine also, no shorts there.

Just tried to hook up my USB flasher to it this morning and it did not detect the NAND. Maybe I have a power issue somewhere, I just can't find it.

Sucks too since this box had some great temps. At least I have a Xenon JTAG still.

 

[Mister_X]

get a multi meter and test standby power to the nand.

And it still could be a corrupt smc, in which case you will have to reflash it.

 

[Martin C]

Well, the thing is, after 14719 update I had FSD running to test temps out after new thermal paste. Then I unplugged it and let it sit idle and unplugged for a day or two. When I went to boot it up again it was completely dead.

As I said, did you unplug the PSU after updating? If not, you were just using the previous SMC and if it was corrupted when you updated it, you wouldn't have known right away.

Can you still read/write to the NAND?

 

[Ir0nman]

If you can read/write I would do a full erase (nandpro usb: -e16)
and then write just Xellous to the nand.

That way you can troubleshoot a bit better. Some here may not agree but, I am just going off of my own personal experiences.

 

[sm0k4 187]

Nope, NAND not recognized. I got it to actually read by applying external 5V and GND from the USB SPI Flasher. I guess I have something to play with now.

Makes sense Martin. After I first did the update, it worked, then I did unplug it for about two days because I was using the legit xbox for Live. When I went to use the JTAG again it was completely dead. So maybe it is corrupt SMC. I will play around with it some more today.

Thanks for the tips all.

 

[Martin C]

No boot and no read/write using SPI = corrupt SMC.

Either erase using a NAND reader/writer (not SPI) or do the bad-flash method and erase the SMC block.

 

[sm0k4 187]

Sweetness. I did the bad flash recovery by shorting the pins to bypass SMC and got the xell image booting. Going to recreate the image with J-Runner and give that a go.

Thanks again!

Now I have E74, haha.

 

[Martin C]

E74 is the eDRAM on the GPU. A reflow might fix it but from experience, you'll need to replace it.