XBox cannot be turned off?

[SluggerB]

So a buddy of mine gave me his OG xbox which was having issues. It suffered from the failed clock capacitor issue, the capacitor had leaked on the board. He opened it up and pulled it off with a pair of pliers. After that, he said he couldn't turn the xBox off so I asked if I could try my hand at it

I ordered up a spare clock capacitor, opened up the xBox and there was a lot of corrosion and damage near the old capacitor location. I cleaned it all up with IPA, and check for continuity between all the components in the area, including through the vias on the board, and everything checks out. I replaced the clock capacitor, and plugged the unit it. As soon as it was plugged in, it turned on, all by itself, and you cannot turn it off. If you hold down the power button, it turns off and back on, by itself. If you select "Shutdown" from the menu, it turns off, and back on by itself. Also, even with the new clock capacitor installed, it is not remembering the time between reboots, it is still resetting

I pulled out the board the switchs are connected to and checked the switches and they check out fine, I thought maybe the power switch was shorted closed but that does not appear to be the case.

I haven't spent a ton of time on it yet, but one thing I found was a chip labeled "203 B10 35CL". When I google that I don't find anything, but if I Google "B10 35CL" I get datasheets that look like this chip, and they tell me that is a schottky power rectifier, with two legs acting as diodes leading to the one leg on the other side. But when I check for continuity and get an Ohms reading on it, I am getting continuity and identical resistance in both directions, which doesn't seem to be right.

Since the clock is not keeping set even with the new capacitor in place, I am guessing that means there is some break somewhere keeping the cap from powering the clock. I dont know if that would have anything to do with the inability for the unit to turn off

Ideas?

[stj]

Re: XBox cannot be turned off?

if it's not a 1.6 board you dont need the cap,
for power button issues, look at the tracks on the underside running along the front edge of the board - they press/rub against the plastic case sometimes and get rubbed through.

and if the psu is foxcon/foxlink and it has any 1800uf caps in it - change them.

[SluggerB]

Re: XBox cannot be turned off?

I got it fixed, it was damaged traces along the board edge. I bypassed them and it turns off correctly now

Odd thing is now, I replaced the clock capacitor, but it still isn't keeping time. I don't know which chip that cap is supposed to be feeding and don't seen anything obvious.any ideas why it isn't keeping time with a new cap?

[SluggerB]

Re: XBox cannot be turned off?

I did some testing and here is what I found: I found the datasheet for the TSOP chip which I think is what stores the time. I have continuity between the negative hole of the capacitor and both of the VCC pins on that chip. I also have continuity between the negative hole of the capacitor and ground.


I had left the cap in the board and left it on overnight, I checked voltage, an it is holding 2.5v, just as it should. I removed the cap and checked for capacitance, and got odd readings. My meter starts at uF, the it changes to mF, and then before any number is shown, it goes to OL. I popped the cap into my component tester and it says "Unknown or damaged part"

Chance I just got a bum capacitor when I bought it off eBay? Or does the continuity between the chip and ground mean there is a short somewhere that is keeping the voltage from getting to the chip?

(The owner is fine leaving the chip out, but I would like to make it completely working if I could)

[stj]

Re: XBox cannot be turned off?

the tsop is the bios,
the clock is inside either the pic mcu or excaliber custom on 1.6

no game or custom bios uses the clock anyway.
it never did hold for long on the cap - that was a design issue

[jayjr1105]

Re: XBox cannot be turned off?

Power issues (can't turn off, turns on by itself) with OG Xbox's usually indicate trace rot. I wouldn't bother replacing the clock cap, just remove it unless it's a 1.6 and in that case you can use a small replacement cap of any variety in it's place.

[RJARRRPCGP]

Re: XBox cannot be turned off?

Power issues (can't turn off, turns on by itself) with OG Xbox's usually indicate trace rot. I wouldn't bother replacing the clock cap, just remove it unless it's a 1.6 and in that case you can use a small replacement cap of any variety in it's place.

I had an old PC case where the motherboard would come back on after pressing the power button! I would have to tap it just right, for the motherboard to stay turned off! LOL