Stranded on highway, alternator or battery…

For the first time in 153,000 miles the 4Runner left me stranded. Tonight, in the rain, after midnight, the dash lit up like a Christmas tree while driving; battery light, ABS, brake, and all the traction control lights. Weirdly no check engine light. I am hoping it is the corrosion on the negative terminal not making a good body ground, but I’m sure it’s time for the alternator. I tried to jump it but it died once the cables were removed.

As luck would have it, no one within 50 miles of me stocks an alternator for the T4R and all dealers are closed on Sunday. Awesome… this looks to be a Sunday full of fun.

 

Sorry to hear. But don’t jump to conclusions. Maybe it’s just the battery went bad.

 

+1 don’t jump to conclusions. If it’s only the alternator the first thing that will happen is the charging/battery idiot light will come on the dash and a voltmeter check will show less than 13v with engine running. It won’t just stop and light up every indicator.

 

Based on your mileage most likely alternator. When mine went out on my FJ, the dash lights came on and headlights went dim while driving it. Luckily made it home. Hope you are back on the road soon!

 

How old is the battery?

 

My two cents on the alternator is that it can sometimes happen very quickly. The time I experienced it on my 2001, the brushes were worn, one of them completely, and the truck died fast. Those are easy to replace if you can find a set. New, they're $20, but even used ones will work if you can get them. Salvage yard? If you have another Toyota, you could borrow them to get your 4R home. Every alternator 'failure' I've experienced has been worn brushes.

 

Brushes in an alternator?

 

Yes. Looks like this.

 

There are several videos. Here's one. If the alternator is being removed anyway, might as well at least look at the brushes before dropping hundreds on a replacement.

https://www.youtube.com/watch?v=qXK...lcGxhY2UgYWx0ZXJuYXRvciBicnVzaGVzIHRveW90YQ==

 

I thought I was the only one who got stuck like that.
Here's my story to keep you entertained while you wait:
Back in 1972, in the Navy, and stationed in Mayport, FL (Jacksonville area). I decided to drive home for the weekend for a "quicky" with the wife (Tuscaloosa, AL) about 500 miles away. I left at 5 PM Friday, was about 11 PM, 200 miles from home, stopped for a soda and gas at a convenience store before they closed for the night. Ford Maverick was dead, wouldn't start and no lights and no cell phones back then. I hitchhiked about 20 miles in to Dothan, AL and sat my butt down in front of a parts store for the rest of the night. About 7 AM a salesman shows up, loans me a battery to try, gives me a ride back to my car, installs it for me, follows me back to the store, and checks out my electrical system. It was only the battery. He sold me a battery and wouldn't accept a tip for his efforts. My being in uniform was the reason. To this day, I never pass a motorist stranded on the highway without stopping and doing my best to help.

 

Also wanted to mention that rapping on the alternator housing with a hammer or something can cause the brushes to 'seat' a tiny bit, maybe allowing you to get home.

 

The thing that’s confusing me about these stories is the alternator stranding people. Usually when they fail they stop charging, idiot light comes on and the car manages to keep going a couple hours until the battery runs down too low to run the ignition.

HOWEVER. I will admit that the last time I changed an alternator it was on a car built in the 1980s… so maybe things have changed…

 

https://youtu.be/fFG7eLAY4m8

Lots of great information here in today's computer controlled cars.

 

Did you ever get a battery light alone while driving, on/off? If so, that's the alternator. If not, that corrosion on your terminal will cause issues. I know because my 06 Civic Si had both issues. The terminal cable, I fixed it by dipping it in boiling water (works amazing). The alternator kept on going on and off until I had it rebuilt for pennies and it kept on going.

 

Must still be sitting on side of road.....NO FOLLOW UP! Guessing at/when parts swapping GETS EXPENSIVE! I would start with battery test. For all we know the serpentine belt could of failed.

 

simple test. get a multimeter and check battery when car off and when car is on and report numbers...
when off should be no less than 12.4v
when on should be between 13.50-14.50v

 

yap. that is the voltage regulator. That is what usually goes on an alternator.. hardly the other stuff like the bearing pulley or diodes...
Was not sure how easily this could be changed on the 4runner.. On some cars it is simply two screws and it plugs to the back of the alternator. and you do not even need to remove alternator.

 

It's been many years but I had the alternator go out on a brand new Oldsmobile. There was no idiot light. Not knowing the problem I kept driving until the engine started bucking on acceleration and eventually died as I managed to turn in front of a line of cars and coasted into a gas station (who wasn't able to help me). The new battery was dead. I put in the battery from my boat and I was able to get to a place where I could get repaired.

The alternator charges the battery but the engine and systems run off the alternator. I have pulled a battery out of a Plymouth after starting it and the engine continued to run. Now my skills are just from my experiences and Toyotas are very different from GM or Chrysler products. My guess is JWhite_TMMI's alternator went out, no idiot light and the battery provided power until it couldn't. A jump start did start the engine but when the cables were removed the engine died. To me, this points to a bad alternator and a dead battery.

BTW, TMMI is the code for the Toyota plant near Evansville, IN, so he must work there....just a guess.

 

I keep expecting my idiot light to come on but, not yet.

 

Actually, brushes and regulator are two different things. All the failures I've seen have been brushes.

 

My bad, replied to another post and forgot this one. Got it home around 1:30am and started on it first thing in the morning. Did the normal tests; battery, fuses, corroded wires. Everything still pointed toward the alternator. Found one 50 miles away, being Sunday I could order it online and still be waiting in the parking lot for the salesman to show. I did just that.

I got the new part home, started to pull parts. Anything I saw that could be in the way of removing the alternator came out. Having my extensive knowledge of Toyotas (more than most) I felt very comfortable removing wire harnesses from the relay box just to save that much more space. It turned a 5 hour job into about a 2 hour job. The hardest part was finding that damn bolt all the YouTube videos talked about. Not removing it, but actually finding it. Other than that, it was cake.

 

Glad you got it. I am curious, though. Did you pull out the brushes to see how they looked once you had the alternator out?

 

I had a 92 4 Runner that did exactly that. It was the alternator that went bad. Easy fix.

 

No, I was done with it once it was all back together. I took it straight back to the store for my core charge.