arfows Posted October 30, 2023 Report Share Posted October 30, 2023 (edited) XBOX 1.2 TSOP flashed with Cerbios that will power up and run for about 2 minutes and then just powers itself off Hit power button again and it powers on right away. This time it stays on for less time...and each iteration of this powers it on for less time than previously until its only on for 15 seconds or so After I let it sit for a half day, it'll run again for a couple minutes and then exhibit the same behavior. This occurs regardless if the DVD is connected during power on sequence (have DVD check bypassed in Cerbios). This sounds like a classic Cap issue...or could it be a power supply issue? To rule out one or the other, what is the easiest way to determine what is giving/causing the power off signal? Thanks! Edited October 30, 2023 by arfows clarity Quote Link to comment Share on other sites More sharing options...
fox Posted October 30, 2023 Report Share Posted October 30, 2023 psu overheating from the sound of it Quote Link to comment Share on other sites More sharing options...
FrostyMaGee Posted October 30, 2023 Report Share Posted October 30, 2023 I agree with @fox It sounds a lot like the psu is overheating. Wouldn’t hurt to double check the mobo for obvious power cap bulges/leakage just to be safe. See if any look similarly wonky on the psu. Check for blocked/dusty vents next to the psu as well for good measure. Quote Link to comment Share on other sites More sharing options...
arfows Posted October 30, 2023 Author Report Share Posted October 30, 2023 Thanks. Should have mentioned that the mobo caps look fine and I've got the xbox opened up, DVD removed, and Hard drive outside the case. Mobo temps are in the 30s (celsius) when it powers off. A quick look at the PSU caps show no obvious issues either. If it is the PSU, what would cause the PSU to overheat, how could I measure that, and is there an easy fix for it? Thanks! Quote Link to comment Share on other sites More sharing options...
sweetdarkdestiny Posted October 30, 2023 Report Share Posted October 30, 2023 Bad PSU caps. Quote Link to comment Share on other sites More sharing options...
arfows Posted October 31, 2023 Author Report Share Posted October 31, 2023 (edited) Will I be ablet to test to see which one it would be? All I have is a simple multimeter. No obvious bulging/leaking etc visible. Edited October 31, 2023 by arfows clarity Quote Link to comment Share on other sites More sharing options...
Marty Posted October 31, 2023 Report Share Posted October 31, 2023 Post of picture of the motherboard. Quote Link to comment Share on other sites More sharing options...
sweetdarkdestiny Posted October 31, 2023 Report Share Posted October 31, 2023 5 hours ago, arfows said: Will I be ablet to test to see which one it would be? All I have is a simple multimeter. No obvious bulging/leaking etc visible. Test the xbox with known good PSU and see if she shuts down. If she works fine you know the PSU caps are faulty. Quote Link to comment Share on other sites More sharing options...
arfows Posted October 31, 2023 Author Report Share Posted October 31, 2023 Swapped with a known good power supply and the same thing happened. First power on lasted about 3 minutes. Each subsequent power on button press lasted roughly 30 seconds. Quote Link to comment Share on other sites More sharing options...
FrostyMaGee Posted October 31, 2023 Report Share Posted October 31, 2023 Hmm. Unless someone has another idea my next thought would be to start replacing the five caps near the cpu on the motherboard. Usually they are bulging or showing some leakage but even if they aren’t it doesn’t necessarily mean they’re good. At this point they either are or are approaching 20+ years old. That’s my thought anyway since you tried a known good psu. Quote Link to comment Share on other sites More sharing options...
ChriZz Posted October 31, 2023 Report Share Posted October 31, 2023 The clock capacitor has been removed and the traces under the circuit board are OK? Quote Link to comment Share on other sites More sharing options...
ChriZz Posted October 31, 2023 Report Share Posted October 31, 2023 Version 1.2 only has 3 capacitors and I remember that I was often able to measure a greatly increased value on these capacitors. Especially the capacitors with metal housing. Quote Link to comment Share on other sites More sharing options...
FrostyMaGee Posted October 31, 2023 Report Share Posted October 31, 2023 2 minutes ago, ChriZz said: Version 1.2 only has 3 capacitors and I remember that I was often able to measure a greatly increased value on these capacitors. Especially the capacitors with metal housing. I was thinking it was a 1.6 but that’s a different post with another power problem. My bad. Yeah I see now where he said it was a 1.2. That being said I’d still probably replace those three and see if the issue remains. Yeah I’d check for trace rot and corrosion around that clock cap too as you mentioned. Quote Link to comment Share on other sites More sharing options...
FrostyMaGee Posted October 31, 2023 Report Share Posted October 31, 2023 Though there are two caps near the mobo power connection I’d replace as well. I believe that’s still the case on the 1.2. I know it is on the 1.6 as I just replaced a few of them on different boards today. Lol Quote Link to comment Share on other sites More sharing options...
ChriZz Posted October 31, 2023 Report Share Posted October 31, 2023 As Marty said above, a decent picture might help. Otherwise we can all just guess riddles. What I would now suspect would be a leaky super capacitor. As soon as the console is turned on, it gets warm and this liquid causes a short circuit somewhere. Which goes faster and faster after you switch it on. Just as he describes it. I would now rule out overheating and thus the temperature sensor since he doesn't mention anything about high-speed fans?! Well let's see what arfows says. 1 Quote Link to comment Share on other sites More sharing options...
FrostyMaGee Posted October 31, 2023 Report Share Posted October 31, 2023 Agreed. A picture of the board and close up on certain areas would be most helpful. Maybe he can post one soon. Quote Link to comment Share on other sites More sharing options...
arfows Posted October 31, 2023 Author Report Share Posted October 31, 2023 (edited) Mobo temps show 30s when it powers off. Also swapped AC cables just to make sure that wasn't the problem somehow but it made no difference. There is trace rot on the bottom, but I cleaned up any fluid residue when I got the box and removed the clock cap about a year ago and the power has stayed on fine until the last week. The only artifact was that the power button wouldn't work and it would only power on with the eject button - but other than that it worked without power loss this entire time Edited October 31, 2023 by arfows addl info Quote Link to comment Share on other sites More sharing options...
ChriZz Posted October 31, 2023 Report Share Posted October 31, 2023 Yes, you can see it well, the ladder rails are through. I would repair it first and scrub it clean generously with isopropanol and a hard toothbrush. Unfortunately, the liquid from the supercap gets under the solder mask and is sometimes difficult to remove. Maybe it's gotten so bad for you over the years that the 2nd PCB layer has been damaged and therefore a short circuit occurs when exposed to heat. Quote Link to comment Share on other sites More sharing options...
Bowlsnapper Posted October 31, 2023 Report Share Posted October 31, 2023 This thread MUST have a resolution. I am staying tuned! Quote Link to comment Share on other sites More sharing options...
FrostyMaGee Posted October 31, 2023 Report Share Posted October 31, 2023 I’d still be tempted to replace at least those three caps near the cpu in addition to what ChriZz suggested. Given their age and all. Quote Link to comment Share on other sites More sharing options...
Bowlsnapper Posted October 31, 2023 Report Share Posted October 31, 2023 12 hours ago, ChriZz said: Yes, you can see it well, the ladder rails are through. I would repair it first and scrub it clean generously with isopropanol and a hard toothbrush. Unfortunately, the liquid from the supercap gets under the solder mask and is sometimes difficult to remove. Maybe it's gotten so bad for you over the years that the 2nd PCB layer has been damaged and therefore a short circuit occurs when exposed to heat. Ladder rails? Quote Link to comment Share on other sites More sharing options...
arfows Posted November 1, 2023 Author Report Share Posted November 1, 2023 I have a second box (the one I pulled the other PSU from) that is now exhibiting the same exact symptoms. That board's middle (of the three) caps has a slight bulge. If I have any spare caps left I'll look to replace that one and see how it goes. From what I have read online, its pretty hard to test caps without special equipment, correct? Quote Link to comment Share on other sites More sharing options...
ChriZz Posted November 1, 2023 Report Share Posted November 1, 2023 6 hours ago, Bowlsnapper said: Ladder rails? Translation confusion sorry Quote Link to comment Share on other sites More sharing options...
ChriZz Posted November 1, 2023 Report Share Posted November 1, 2023 15 minutes ago, arfows said: I have a second box (the one I pulled the other PSU from) that is now exhibiting the same exact symptoms. That board's middle (of the three) caps has a slight bulge. If I have any spare caps left I'll look to replace that one and see how it goes. From what I have read online, its pretty hard to test caps without special equipment, correct? You need an ESR meter for this. This shows you the Value like capacity and vloss value. If you install new caps you have to take ones with low ESR, hope you are aware of that. Otherwise you will create a new error. Greetings 1 1 Quote Link to comment Share on other sites More sharing options...
FrostyMaGee Posted November 1, 2023 Report Share Posted November 1, 2023 16 minutes ago, ChriZz said: You need an ESR meter for this. This shows you the Value like capacity and vloss value. If you install new caps you have to take ones with low ESR, hope you are aware of that. Otherwise you will create a new error. Greetings Just to add on to what you’ve said he would also need to have the same temp rating (or at least no less than) which I believe is 105 C on those caps. Also an equivalent microfarad or above and same with voltage obviously but I assumed he was doing that already. I prefer to keep them on spec with the last two but have sometimes used 3300 microfarad 6.3v to replace the older 1500 microfarad 6.3v caps. 1 1 Quote Link to comment Share on other sites More sharing options...
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