Virgin Wii Turns off after 30 Seconds

I bought this Wii in July of last year from a liquidation sale. My cousin just started helping me out with Wii drive changes and basic repairs. We found one that turns on for exactly 26 seconds before shutting off. The video instantly goes out after 1 second though(I got it to stay on one time long enough to see the introduction Wii setup screen when you first turn on a formatted Wii), but the power cutout after 26 seconds, and I can't get any video now. I can sync remotes with the Wii, but I can't power the Wii on and off with the remotes, and I have to resync every time I power on for those 26 seconds that I have. I'm wondering if the Wii is losing power when the current reaches a fuse, capacitor, or resistor after that time. I'm also curious why the video won't show up anymore as I've never seen a brick that shuts down the Wii(light goes from greenish yellow to red after 26 seconds).

I have another Wii that instantly shuts off(red light turns yellow, the disc drive blue light flashes, and then no light at all after 1 second). I swapped drives, but that didn't do anything. Is this another fuse issue that needs to be tested with a multimeter?

Fuses don't work like that, once they blow the item they are protecting will stop working. There are fuses that can trip and reset but I doubt the Wii has any of those.

If the Wii is coming to an on power state and failing once loaded then I would be looking towards overheating issues. The Wii doesn't produce all that much heat, after all the total power usage is only 18 or so watts, so I'd imagine that it's not a dodgy fan as that would take several minutes to cause an issue.

It could be a dodgy heatsink on CPU/GPU. It uses an passive aluminium heatsink sitting atop both chips, if this was loose and not making a contact on either or both chips then they would shut down very quicky. I'm not sure about the retention mechanism for the heatsink, it may only be epoxy glued.

For " ...have to resync every time I power on for those 26 seconds that I have....." , check the button cell in the compartment at Wii side, near Eject.

Are u sure the mini-fan working fine ?

As Tealc has mentioned, resettable fuse (or PTC fuse) is applied in Wii console. [correct me, if wrong.]

I considered a fan issue for the one that always lasts 26 seconds, but the black fan in back seems to be circulating cool air during that time. I can replace the fan, but I'm not sure if that will fix the problem as the Wii should be able to run without that fan in. I'll examine the heatsink for loose screws. The exact timing if this Wii was so odd though. I'm happy to report that my cousin fixed three Wiis today by swapping the bluetooth modules and am waiting on the mod chips to see if we can fix the other two without video or sync of the remotes. I seem to recall one this week that had no video but synced remotes, so maybe that's a faulty connection with the video plug. Thanks for the help here.

For the one that turns off instantly(seems to be a common problem among broken Wiis), you would also suggest examining the heatsink and not the fuses with a multimeter, right? I also posted a question about the Wii Balance Board that detects weight when no weight/force other than gravity is present on the board. The only way around the problem is to hold the board in the air, but I think that would affect some games. I'm wondering if I could remove a certain component or reset it to the default state. That component is probably permanently fried though. I will take pictures of the circuitboard and post them in my main Balance Board topic.