Mega stupid mistake

Update us when you tested the fuses. I would opt to replace those fuses with new ones just to be sure. The relays could be busted, too!

 

yes, I was going to ask that. I just replaced and tested all the fuses and they are good. Do you think the relays could be what’s causing this.The car turns on, And the gauge cluster turns on. Nothing else works, though inside the car. The windows do not the radio, the air conditioner, and Put it into drive.

 

Trying to clarify here. This is where you are:

Car turns on. (does it also start and run?)
Gauge cluster turns on
Windows don't work (locked or unlocked?)
Radio doesn't work (no power or lights?)
A/C doesn't work (meaning the fan? Does the A/C indicator LED light when A/C is selected with the fan set to ON?)
You can't put the shifter into drive (with the brake pedal depressed?)

What about other items, such as turn signals/flashers (do they flash fast?), headlights, high beams, power seat, sunroof, mirrors, anything else electrical?
Are there any aftermarket electrical items such as alarm, remote start, etc.?

Do you know what relays the car has?

 

Any update?

 

Pretty much yes, the gauge cluster is the only thing that turns on. Nothing else on the dash, windows do not go up and down, I can’t put the car into drive, the brake lights or turn signals don’t work either. the headlights do turn on.

 

If it was me, I'd get a notebook and start from ground zero. I would try every item, one at a time, and write it down along with the symptom it produces. Take your time and be thorough. Try every electrical thing that the car has, and write down what it does. After you've made that list, make another page. On that page, list the items on the left that don't work, and the ones that work, list on the right. You'll end up with a list of items on the left that don't work, and some of them will have a common denominator. Then start researching things they have in common. For example, the truck starts and runs, but you can't get it into gear. That procedure requires a functional brake pedal switch. Also, the brake lights don't work. That requires the same switch. So maybe the switch or associated relay got damaged, or a bulb shorted badly and is damaged, or something.

That's how I would approach it if I had limited knowledge of the circuitry, since you said you've already eliminated all the fuses as suspect.

 

There is an electrical wizard on this site. He saved me. @Old Red Wonder if he can give some advice.

 

Oh, this is somewhat out of my wheelhouse as I am not as familiar with the 4th Gen vs. 5th Gen. What year 4Runner are we dealing with?

I think the advice so far given in this thread is a solid place to start. You need to check every fuse in both the engine bay and cabin with a multimeter. You will likely need to replace the vast majority of them. Once you know that power is reliably getting to every system, then we can start trouble shooting things individually. My guess is that you blew the majority of the common fuses like ECU-B, Door lock, IGN, ACC, etc. and that is why very little is working. The ECM is likely not getting any power either, and shares some of those common fuses.

Once power is supposedly getting to everything, then the real damage (if any) will be apparent.

Keep us posted.

 

I appreciate you all for the help. I am stumped myself. I replaced and checked all the fuses including the 140 alternator fuse, which was blown. At this point, I am reaching out to a mechanic. I I’ll keep you posted.

 

Good call. You tried your best. Seriously. At some point you have to hand it off. You did well. Please please let us know what the fix was. I have a feeling someone will need the advice in the future

 

Hey before you give up. Did you try replacing the negative cable from the battery? Just grab one (any one) from Walmart hold it to the terminal and to ground on the body. If it doesn’t work, return it. Here is my thought on this. You energized that cable. You could have shorted that out. But I do commend you on your effort

 

Interesting, it’s worth a try. Now, if the negative cable was bad, would the car still turn on?

 

great question. The short answer is I don’t know. Are there any additional wires grounded to that same ground point besides the battery cable? My thought is you energized that line or lines when you put it on the positive.

 

It’s still worth trying, I will let you know. also, the mechanic came by and he could not plug in the diagnosis tool under the dash. The plug was also not working.

 

Does your vehicle have any fusible links? They look like short wire splices.
I also wonder if the reverse voltage may have damaged one or more of the ECM modules. Have you tried "reading" the vehicle from the CAN bus connector?

 

I feel for you brother. I really do. Im trying my hardest to help you. There is one more thing I would try but no guarantees. On YouTube there is a channel called Viking Garage. Pick any of his videos and ask him where you should look next. He is a Toyota certified technician and 4Runner owner. Ask him. He is a real cool guy and always responds but again no guarantee. Were there additional wires grounded to the ground point?

 

That’s an excellent point. I did something similar as this but on a MDX. With mine though the OBD2 was still working. But I shorted a wire to the ECM.

 

This was my thought but I don't remember if the 4th gen had them like everything before it. Ironically I turned wrenches for Toyota when the 4th gen was nearing the end but as expected, they weren't in the shop often outside maintenance.

For OP, I'd start at the battery and probe as you go... check the fat wire at the fuse block, alternator, and starter for 12v hot on multimeter (not a test light), then all the fuses with ignition on if those are good. Focus on the essentials that run the truck but if you're getting cluster and nothing else, I suspect you may have a problem with power to the primary fuse box since cluster and gauges run off the interior block.

 

sub'd

 

Thanks man, thank you to all who have tried to help. The mechanic thought it could have been the body control module, although he was stumped because the gauge cluster works through it and it works. Since the OBD2 didn't get any power, he couldn't confirm.