A golden oldy question.

2004 4runner Limited with an issue. For some reason (Could be the new LED head/tail light install) the windows and sunroof stopped working. If I cut off, and remove the key, swap out the 10 amp fuse and start it back up everything works fine, then for no rhyme or reason they all stop working until I swap out the fuse again.

Have done the battery reset trick rolling half way down and then back up holding for a second with no luck. I thought maybe a short, but then why would it work when I swap out the fuse, and the fuse is always still good, never blows.

Anyone ran into this issue, as everything I read online is of a different problem not the same as mine, and suggestions or help would be greatly appreciated.

 

So if you didn't have the problem before the LED headlight/taillight upgrade then my best guess is there's the issue. Did you try swapping them back? This is exactly why I hate electrical when doing my own work on my vehicles!!!

 

That's a question for the 'electrical pros' here. I wonder if any related relays may be overheating and staying open? White Walker's idea.... yep, try that.

 

Welcome! There are a number of wiring knowledgeable folks here.

 

Honestly, relays are pretty immune to heat. Not completely, very few electronic components are, but pretty immune.
What they are vulnerable to, more than anything else, is age, closely followed by corrosion.

I would replace the relay with an OEM one. If you choose, you can pull the casing off and check the contacts for corrosion build-up. They can be cleaned with some fine grit sand-paper, or ruby cloth. You can also ohm the coil out. It shouldn't be much more than 1-3 ohms resistance. Much more, the coil is bad, much less, it may be shorted. All a relay is is an electro-magnet, after all. If the coil has gone south, it no longer magnets, if that makes sense.

Generally though, it's the contacts build up corrosion over time. Every time they make, and break, a microscopic spark jumps the contacts, and every time deposits a tiny amount of crud/corrosion on the contacts. Enough builds up, the current can no longer pass through the contacts. If moisture gets in, and most relays aren't sealed at all, it will accelerate the process. High humidity, water intrusion, etc.

Finally, check the contacts where the relay plugs into it's socket. Same problem there. Corrosion/dirt buildup. Just as easy to clean.

Sorry, I'll shut up now...
Pat☺

 

Wondering if you need to wire in resistors for the ECU to read the correct resistance. I have no idea if the circuits are related but I just ran I to an issue similar to this on my ford pickup. Installed a flatbed with LED lighting and found the brake light circuit was connected to several other circuits.