I was at autozone today to have my battery and alternator tested. The battery tested ok, but when he put a load on my alternator, the truck shut off. When I went to crank it back up to go home, the battery was dead. The autozone guy brought out one of those battery powered jumper things, and while I was sitting in the cab about to crank it, he managed to connect the wrong cables to the battery. I saw smoking and sparking, jumped out, and showed him the mistake.

Finally got the thing cranked, and my battery light was on and the truck was loping. I hung around the parking lot for a minute, then headed home at about 50 mph, and the truck evened out, the battery light went off, and I made it home. Back in the driveway at home, I was able to crank it and turn it off a couple times before the battery died (i.e., the original problem, as expected).

What should I look for, damage-wise, that he might have screwed up on my truck from crossing the jumper cables?

 

never ever accept a jump with out checking the hook up yourself

 

Yes, I learned that lesson today. Hopefully it wasn't an expensive lesson.

 

Seems like Autozone should pay for any repairs

 

I've heard that it can possibly fry some of your electronic system. Check all your fuses and relays to make sure it's okay.

 

I work at Autozone in Washington and if you talk to the store manager at the

location or get the number to the district manager ( number should be posted

on the door) he might replace the broken parts,fuse,relay etc or at least

give you a gift card to use at the store. Thats what they do up here.

 

well it could of damaged many things, the one big danger altho rare but can happen is it can actually surge ur computer. But it sounds like your battery is not holding a charge and ie theres a voltage draw ( paracitic draw ) on your battery. do u have any aftermarket electrical components such as a stereo, off road lights or after market gauges??

 

No aftermarket electronics at all. Nothing's plugged into the 12 v outlets. The Autozone guy said the battery was fine, but when he put a load on the alternator, that's when the truck shut off. He said I need a new alternator.

 

I did this by accident once (never try to change batteries in the dark and with two different styles of batteries.) I blew the regulator in the alternator. Why did you have it tested to begin with? was the alt/batt light on before you went there or only after he hooked up the battery backwards you never did say.

I agree if you complain to management at autozone, they should replace the alternator or pay you to have any other electrical troubleshooting that needs to be involved if it didn't just blow out the alternator.

 

The battery tested ok and the alternator tested bad BEFORE he crossed the lines jumping me off. The battery light came on briefly after the bad jump, then went off once I started down the road.

The original problem was the 4runner would not start. I just got a rapid click-click-click-click-click-... from the starter. The battery was also very low (e.g., I tried the wiper blades, and they moved slower than normal). As I understand it, the clicking was the starter trying to engage, but it didn't have enough juice. I cleaned the battery terminal connections. The starter is a Bosch replacement from 3 years back, mechanic-installed. The battery is at least 4-5 years old, maybe older, I've forgotten. Alternator is the original one, I believe. 163k miles on it.

I'm thinking I need to start by replacing the brushes in the alternator.

 

that sounds like a good idea and since your battery is that old and when he applied that load he might have fried a cell in the batter which after that happens they are no longer good

 

I'm praying it's just a $20 brush swap job. I'll know more next week when I finally have time to fix it.

BTW: Kerby J - I love your avatar. Looks like a fun trip in the snow.

 

If your alternator was not working your battery was dead enough you needed a boost. The same person did the test that got the cables on wrong!!!

Then you say the low voltage light went out on the way home ??? If the alternator is Kaput as they say the light would not go out . And as soon as the voltage dropped low enough the computer drops off line.

You are along the road.

Look at your ground cables look at the plug into the alternator . The wire off the B terminal to the fuse block. All these can cause your issue.

If you don`t all ready have a multimeter now would be a good time to get one Then do your own testing.

Good luck

 

sounds like yur brushes are toast, maybe the rest af the alt too. if the light comes on and goes off when you tap on the alternator, it brushes, i would start there no need to throw money at it. fully charge your battery and with a working alternator you couold very well be fine

 

4-5 years is pretty old for a battery, is it not? I'd say that is your most likely culprit, especially since the battery light went off and you were able to start it at home. Keep in mind that colder weather makes the chemical reactions in your battery less efficient, so it is able to deliver less amperage on a cold crank.

 

I'm back home after a trip, so this week I'm going to have time to address this finally. My first goal is to swap the brushes in the alternator. Since I'm already going to have the alternator off, are there any other easy checks or maintenance tasks I could take a look over at the same time?

Toyota OEM alternator brush and brush holder assembly (no solder needed; bolt in) - $22 @ stealership
P/N 90430-12031 for 1999 4runner 2.7L engine


gdutch, all I can add to your question is that the battery tested ok and the alternator failed under load, so my feeling is that the alternator isn't continually recharging the battery, probably because the brushes are not making good contact. If the brushes don't do the trick, I'll get it re-tested, but based on what I've been told now, the alternator's the likeliest culprit.

 

If you have the alternator off take it into autozone and have them bench test it. Takes about 10 minutes. Also can take the battery in and then charged and tested also just to make sure. That normally takes about an hour.

I have worked at autozone twice and I accidently installed a battery cables wrong....long busy day.....and had to replace the main fuse. Also did that in a Honda a long time ago when installing an Optima not orignally for that car and blew the main fuse but your car won't start after that.

 

What a monumental PITA. I removed the alternator a few minutes ago to replace the brushes.

I got the alternator off after fighting the lower bracket bolt for a couple hours. First the rear nut wouldn't come off. Then, the bolt didn't want to back out of the bracket (even with me hammering on it). Time includes a trip to Sears to get a ratcheting screwdriver that I thought might be useful in trying to install the new brushes while the alternator was still in place (too short, of course). Of course, one of the screws that holds the bracket is stripped, so I still had to get the bloody alternator off.

That lower bolt and nut were really really tight/corroded together. I had to get a foot up on the tire and push while I pulled the wrench. That sucked.

The worst part is, although the workspace was really tight, I think that if the small screw on the brush holder wasn't stripped, this could have been a 20 minute job with the alternator not being removed. I don't know if I stripped it, or someone previously changed the brushes and stripped it then. I don't think I was cranking particularly hard on the screw.

These are my old brushes (right) compared with the new ones (left). The old ones are worn in a curve, with 5 mm of brush exposed (from the base to the bottom of the curve). The new ones have around 11 mm exposed, and are flat on the top. Mountaingoat wrote in a previous thread that the FSM minimum specs are 1.5 mm exposed, so I suppose this could mean it's not the brushes. Guess I'll bring it in and have it tested since it's off the truck anyway.

 

.....

 

If you think there may be damage, i would get written confirmation that they would pay for a toyota dealer diagnostic and any repairs that may have occurred from the employee.