1998 Limited electrical drain - seeking troubleshooting tips

My first post so be gentle (I did run a search first, but...)!

1998 Limited. Battery gets drained and I haven't been able to figure it out. Yet. Put in a new battery and when it sits for a couple of days, it's dead. Repeated, so not a battery issue.
No lights left on that I can tell. After-market stereo that I'll be reverse installing this weekend to see if maybe something there.
Are there any tools that I could use to hep figure this out? (remember, gentle: I'm an accountant, not a repair-guy) E.g. something I could use against the fuses to see what is 'hot' when the car is off? Or is this is matter of just trying to troubleshoot everything electrical in the vehicle?
My youngest is getting his permit soon and has already attached his gym fob to the key-chain so I/we need to get this issue resolved. Any tips would be much appreciated!

 

If you haven't used an ammeter (volt meter type), might be good to get a buddy who has, especially if he has a meter too. You remove the negative battery terminal, clip one meter lead to the cable and the other to the battery terminal. You'll want the meter set to a low AMPS range because you're looking for milliamps. If your meter has a fuse, buy more fuses first because it's common to blow them. A dome light will do that, which is why you need to turn everything off. It's a good idea to open the two front doors and turn off the dome light, plus radio, fan, anything that uses electricity when the key is turned on. When you're ready, turn the key to ON (don't try to start the engine) and look at the reading on the meter. If it's over, say, 100mA (likely more), begin to pull one fuse at a time looking for that number to go down. When it goes down to a normal range, you've found the general area of the problem. 50-70mA is typically OK. Now you have to troubleshoot the faulty circuit. If the display goes blank, you blew the fuse in the meter.

This should get you close. Like I said, having someone familiar with doing this is a big plus. Hope you get it figured out!

 

Just an FYI, the reason you don't start the car with an ammeter in series with the battery, you will blow the meter. It will pull like 40Amps when starting. If you can get a multimeter with a clamp on ammeter, that usually works better when you don't know how much current you're dealing with.

Disconnect ALL aftermarket stuff. All USB\Power Ports\Cameras\Radios\etc\etc. Aftermarket crap is OFTEN the cause. Typically the cheap Chinese device goes bad or the installer just hacked at the wiring harness and you have a wiring issue.

On these cars, the in-series ammeter test does work but you can do it a bit easier by measuring voltage drop across the fuses. This works better for modern cars that will run systems even when the car is "off". You will need to measure voltage across fuses and then compare to a chart. For modern cars, you may have to wait an hour for the on board systems to settle down. For 3rd gen 4Runners, the car is off when the key is off so either way works. I do like the in-series test IMHO.

https://www.youtube.com/watch?v=lRcj1fQcWwU

 

Maybe I’m wrong, but I thought clamp meters weren’t very accurate with tiny currents.

 

Probably not, but I think they've gotten a lot better? I see some lower amp ones. I just use the old one I have to make sure the draw is not going to wreck my meter before I go in series.

 

That's an awesome video, thanks! I love when it's explained in a way that all audience members can follow along. I've got some great ideas of where to begin, hopefully this weekend. I'll keep y'all posted. TY!!!