Electrical Drain

[Myrunr2010]

I'd like to revisit something you said in the first post. How often are you driving your 4runner? Once a week? Once every other week? Once a month? I'm really leaning towards the issue that you aren't driving it enough.

I went through the same issue a few years ago. I was positive that I had a drain, and pulled my hair out trying to figure it out. The issue ended up being that my 4runner wasn't driven enough, and the battery wasn't charging. I'm in the same situation right where it's only driven once every other week, and now I have it hooked to a trickle charger.

Mike

Well, battery was dying if it wasn’t driven every 2-3 days. Once I gutted everything it was down to a 6-7 days. I wouldn’t think a new battery would lose juice enough in that time period to not be able to start, but it is something to think about if I can’t seem to figure anything else out.

 

[Myrunr2010]

Just a short update. Since I hooked up the multimeter and was pulling fuses, I’ve left the “dome” fuse out. I haven’t had any issues with battery drain since doing so. I haven’t had the chance to diagnose any further, but my assumption is it’s something with the radio. Dome lights, radio, clock, and door locks are all out, radio seems most likely.

 

[DaMonkey]

Just a short update. Since I hooked up the multimeter and was pulling fuses, I’ve left the “dome” fuse out. I haven’t had any issues with battery drain since doing so. I haven’t had the chance to diagnose any further, but my assumption is it’s something with the radio. Dome lights, radio, clock, and door locks are all out, radio seems most likely.

You’re doing a great job troubleshooting. Your assumption about the radio is reasonable, however with only 20 mA drain it sounds like your problem is intermittent. And it is within the dome fuse. Any one of those items could be intermittent.

I have not had the problem, however dome seems to be a trouble maker on these. Maybe try disconnecting power individually to radio and leave dome fuse in to see if that does it.

Electrical can be a headache and intermittent is the worst kind. You’re almost there

 

[Myrunr2010]

You’re doing a great job troubleshooting. Your assumption about the radio is reasonable, however with only 20 mA drain it sounds like your problem is intermittent. And it is within the dome fuse. Any one of those items could be intermittent.

I have not had the problem, however dome seems to be a trouble maker on these. Maybe try disconnecting power individually to radio and leave dome fuse in to see if that does it.

Electrical can be a headache and intermittent is the worst kind. You’re almost there

That’s the plan since the radio will be the easiest thing to rule out. Planing to just pull it out/put the dome fuse in, and leave it like that for a while to see if I have the same power draw. We’ll see though.

Assuming it is the radio...that would likely be an issue with the radio itself, right? Not something with the power leading to it?

 

[DaMonkey]

Assuming it is the radio...that would likely be an issue with the radio itself, right? Not something with the power leading to it?

if you disconnect power to the radio from right behind the radio (just pull harness out) then it must be radio because that's the only thing between power and ground.

if you disconnected isolated radio power upstream somewhere (behind fuse panel or something) and it fixed the problem, then your problem could be anywhere between where you disconnect and ground (at the radio). but that's real hard to imagine because the only place for that current to go would be a direct short from bad wire and would blow the dome fuse.

just pull harness out of radio. bezel is real easy on mine, but it might be possible to give her a reach around to pull the harness out. if you can reach it, and there are 2 harnesses, power is in the bigger harness of the two.

because it's intermittent, i have this creeepy feeling that it's a bum door switch that is intermittent. my first isolated target i think would be to pull the dome bulbs out and put dome fuse back in. i haven't taken a look at the circuit, but i think those go back to the door switches and those are switches that go through a lot of cycles and prob more apt to go bad. but you're whittled pretty far down the road.

 

[Myrunr2010]

Well, the radio has been out for months now and I haven’t had an issue with electrical drain. It’s been so nice to get in and turn the key and it just work that I’ve been afraid to put a new radio in, lol. I’ve pulled the trigger though and will be replacing it once it comes in. There’s a part of me worried that my electrical drain will come back with a new radio though.