Car shuts off after engine rebuild, any ideas?

I recently rebuilt the top end of my 2011 Toyota Corolla Le 1.8l engine. Everything went smoothly during the rebuild and the car started without issue. However, after about 5 minutes of idling, the car just shut off without any struggle or misfire. I started it again, and it ran fine for about 30 minutes until I turned it off for the night. The next morning, I tried starting it for a test drive, but it shut off again after idling for about 10 minutes. When I tried cranking it, the car wouldn’t start. On the second crank attempt, the dash shut off and wouldn’t turn on, and now there’s no power to the interior – no lights, no dash, no AC, nothing. I’ve checked all the fuses in the engine bay and interior fuse box, and they look fine. The battery’s reading 12.46V. The engine bay fuse box seems to have power, but there’s nothing in the interior fuse box. I found that the two grounds on the valve cover were loose, but everything else seems secure. Anyone have any ideas on where I should start looking? My guess is a wire might’ve melted or the ECU might have fried, but I would’ve expected a fuse to pop first. Any advice would be much appreciated. Thanks!

Does the long fuse block have a clear plastic cover? It’s hard to tell if any of the filaments are broken without removing it. On my 2010, there was a plastic arch locking the cover in place, and I had to cut it off to access the fuses.

Also, don’t forget about the relays. They can be tricky to check, but you can test them by checking the resistance across certain terminals or applying power to listen for the switch.

@Wil
The fuse block is in good shape, and I used a multimeter to check the tabs, confirming they aren’t blown. I’ll give the relays a shot and see if I can test those next.

Well, it’s definitely something.

Teal said:
Well, it’s definitely something.

Haha, I guess so.

Teal said:
Well, it’s definitely something.

This made me laugh, good one bro.

Teal said:
Well, it’s definitely something.

If the issue continued even after tightening those wires, I’d suggest checking the battery. It might seem okay when you test it, but it could still be worn out and not have enough power to run everything.