Help, blew 140 amp alternator fuse cuz I'm stipid

[Wile.E.Coyote]

Was trying to wire up second battery and accidentally reversed connections. Blew fuses including the major 140 amp alternator fuse. All I could find was an old thread saying that you need to remove the top half of the junction box to get to a couple bolts holding the alternator fuse in but I can't figure out how to get the junction box apart. Engine starts but won't shift from park and dash lit up like Christmas tree. Hopefully just relaxing alt fuse fixes everything but any help is appreciated.....

 

[CXS]

It's stipid to relax alt fuses!

:sorry:

 

[Wile.E.Coyote]

I suppose it would be inadvisable to solder the fuse?....

I got the junction box apart but I don't see any way to get the bolt that holds the fuse in from the inside.

 

[dkyleb]

Hey man. You're not the first one to do it. I did it too... and so have other people.

Separating the fuse block is a nightmare. Toyota has a sweet SST for doing it, but we don't get that comfort! Here's the best image I could find:

IIRC, there are 3 or 4 tabs you need to somehow release, and pull on the top section of the block to separate it from the bottom section. I had another person helping me. Just keep messing with it, you'll get it to separate eventually.

 

[Wile.E.Coyote]

Thanks man I got it apart, can't get to the fuse bolts though. Don't know how they got them in there. I soldered the fuse connection and it runs fine but sometimes MIL comes on and all the other lights are on- abs, trac, vsc, 4lo, even the ebrake. I went to pull codes and the reader isn't getting power from the OBDII, so I don't know what the fack is going on.

 

[dkyleb]

Thanks man I got it apart, can't get to the fuse bolts though. Don't know how they got them in there. I soldered the fuse connection and it runs fine but sometimes MIL comes on and all the other lights are on- abs, trac, vsc, 4lo, even the ebrake. I went to pull codes and the reader isn't getting power from the OBDII, so I don't know what the fack is going on.

No, you didn't get it apart. That's how you get to the nut holding the fuse in. The whole thing separates.

You soldered that fuse??? WTF? That's not a good idea...

It also sounds like you may have fried some stuff... Better hope you didn't accidentally hook those batteries up in series and make a 24v system.

 

[Wile.E.Coyote]

Yes, soldering clearly not advisable. Understood. What could I have fried that would cause: no radio, no hvac, no 12v power, lights on dash, no power to OBDII, shift linkage lock, no turn signals?

I've checked all fuses at least twice.

 

[Wile.E.Coyote]

No, you didn't get it apart. That's how you get to the nut holding the fuse in. The whole thing separates.

You soldered that fuse??? WTF? That's not a good idea...



It also sounds like you may have fried some stuff... Better hope you didn't accidentally hook those batteries up in series and make a 24v system.

I've gotten all 4 clips and can pull it out enough but how do you remove it completely, do you have to disconnect the wiring on the driver front side?

 

[Slowgoat]

Hope you get it figured out.

Sub'd.

I'm rooting for you man!

 

[Wile.E.Coyote]

Soooo, I re-soldered the fusible link and it appears to have fixed all problems except my radio has no power. I don't think the soldering is as big a deal as it sounds, the fusible link seems to have 2 break points based on where it blew originally, I soldered that point so it leaves the other. It's a temporary fix anyway because.....the gawdamned fuse is impossible to find! I went to 4 auto parts stores and looked online and the best I could come up with was an old eBay listing. Guess it's off to the dealer this week.

Now I just gotta figure out the radio...

 

[dkyleb]

Soooo, I re-soldered the fusible link and it appears to have fixed all problems except my radio has no power. I don't think the soldering is as big a deal as it sounds, the fusible link seems to have 2 break points based on where it blew originally, I soldered that point so it leaves the other. It's a temporary fix anyway because.....the gawdamned fuse is impossible to find! I went to 4 auto parts stores and looked online and the best I could come up with was an old eBay listing. Guess it's off to the dealer this week.

Now I just gotta figure out the radio...

When I blew mine, I found it at the first auto parts store I went to... :shrug:

 

[chips2002]

The radio usually has a fuse on the back. You would have to remove the radio and check that the fuse has not blown. Before you do that, there is another fuse near the engine compartment or inside underneath the steering column.

 

[Wile.E.Coyote]

The radio usually has a fuse on the back. You would have to remove the radio and check that the fuse has not blown. Before you do that, there is another fuse near the engine compartment or inside underneath the steering column.

Thanks, the 2 radio fuses are in the engine compartment junction box, but those are both fine so I'll pull the radio and check. Thanks!

 

[BlackWorksInc]

The radio usually has a fuse on the back. You would have to remove the radio and check that the fuse has not blown. Before you do that, there is another fuse near the engine compartment or inside underneath the steering column.

This is mostly true of aftermarket units and some older radios. 4th gen radios do not have one on the unit.

 

[BlackWorksInc]

Soooo, I re-soldered the fusible link and it appears to have fixed all problems except my radio has no power. I don't think the soldering is as big a deal as it sounds, the fusible link seems to have 2 break points based on where it blew originally, I soldered that point so it leaves the other. It's a temporary fix anyway because.....the gawdamned fuse is impossible to find! I went to 4 auto parts stores and looked online and the best I could come up with was an old eBay listing. Guess it's off to the dealer this week.

Now I just gotta figure out the radio...

The soldering is unreliable best case scenario it works as intended, worst case it doesn't blow at the required 140amps fast enough and puts that current through the system.

 

[Wile.E.Coyote]

[MENTION=66389]BlackWorksInc[/MENTION]. It's an aftermarket radio and I'm fully aware of the risks re: soldering a fusible link, but I appreciate the concern.

 

[Oldmannewercar]

The battery on my 2016 4Runner ran down. I was in a hurry to get a perscription for my wife. I took the battery off my travel trailer which was the same size and put it in the 4Runner. Like I said I was in a hurry and didn't notice that the positive and negative terminals were at opposite ends. The 140 amp fuse blew. I soldered a new 140 amp fuse across the blown fuse. Now the engine turns over but won't start. The radio also doesn't work. I live far from any dealer and don't want to pay a tow company. Thanks for any suggestions.

 

[evan1242]

The battery on my 2016 4Runner ran down. I was in a hurry to get a perscription for my wife. I took the battery off my travel trailer which was the same size and put it in the 4Runner. Like I said I was in a hurry and didn't notice that the positive and negative terminals were at opposite ends. The 140 amp fuse blew. I soldered a new 140 amp fuse across the blown fuse. Now the engine turns over but won't start. The radio also doesn't work. I live far from any dealer and don't want to pay a tow company. Thanks for any suggestions.

There are likely more fuses blown else were. Need to check them all.

 

[Oldmannewercar]

I found another blown fuse. Now everything seems to be working but still won't start. I pulled the ign fuse and another fuse under the dashboard, they were ok. I really need to get it running today. I will keep looking. Thanks.

 

[Ericballz]

Anyone got any further tips to separate the fuse box to gain access to the 140 amp fuse? I’m ready to rip the box apart after trying for the past day and not getting it to separate.