Is my alternator about to go? (1 Viewer)

[Gamecocks910]

2004 LX470. New battery replaced 3 months ago.

Symptoms are battery light coming on at idle (on occasion) and I can see the battery voltage meter dropping down to what I think would be around 11ish volts. Car starts perfectly and never dies when the batt light comes one. Grounds and batt connections are cleaned and look fine. Not sure how to check the fuse block thing connected to the + batt terminal but the fuse in the main fuse box is in tact.

Is this a warning sign for alternator to go?

 

[BnvS]

So I think this is one of the warning signs..this happened to me on my Tundra 4.7l. Similar where the battery dial would fluctuate and the battery light did come on while driving.

3 more test to do...I say this b/c I replaced 2 alternators just last month on my LC and T100.

1. While your car is running check how much voltage you are getting on your battery terminals. if its less than 13.2V or lower.. your alternator is going to go or close to it.
2. Just take it to an autoparts store and get it tested. They will have a load tester that would see if the alternator is not putting out the correct amount of current to keep the battery charged.
3. Take the alternator out and take it to autoparts store to get it bench tested.. this is the ultimate solution to ensure if its your alternator and not your battery.

 

[Gamecocks910]

So I think this is one of the warning signs..this happened to me on my Tundra 4.7l. Similar where the battery dial would fluctuate and the battery light did come on while driving.

3 more test to do...I say this b/c I replaced 2 alternators just last month on my LC and T100.

1. While your car is running check how much voltage you are getting on your battery terminals. if its less than 13.2V or lower.. your alternator is going to go or close to it.
2. Just take it to an autoparts store and get it tested. They will have a load tester that would see if the alternator is not putting out the correct amount of current to keep the battery charged.
3. Take the alternator out and take it to autoparts store to get it bench tested.. this is the ultimate solution to ensure if its your alternator and not your battery.

Should be able to tackle 1 and 2 today. After recently selling my truck to capitalize on this market before its too late, this has turned into my daily driver so I most likely cannot do #3. Wife is due in 3 weeks so I can't be stranded without a car. If Im that far into it, I might as well just swap it out.

Thanks for the advice, hope to update here soon,.

 

[BnvS]

@Gamecocks910

Buddy.. your playing at the wrong time... lol but no worries you still got time..lol as I said I did 2 alternators last month so I know the drill.. but one thing that stung me when I replaced my T100 alternator was that my battery on the truck also went bad too. and I got to know it after i swapped my alternator...So my advice is if you know your alternator is bad..obviously swap it..but also make sure your battery is in good shape as well... you don't want to just swap the alternator and call it a day...especially not in your situation.... I upgraded my LC alternator to a 130amp ver.. so that was nice.. both working perfect after this work.

Good thing is swapping the alternator is not too bad on the LC/LX.. although you still have to remove the lower fan shroud to get enough space to take it out.. if you are doing the work yourself.. watch some videos on whats the best way to do it. And I would advise on getting the Denso reman for sure....so you dont have to do it again in 4 months..

and finally and Good luck on both...especially the little one..

 

[Patassa]

2004 LX470. New battery replaced 3 months ago.

Symptoms are battery light coming on at idle (on occasion) and I can see the battery voltage meter dropping down to what I think would be around 11ish volts. Car starts perfectly and never dies when the batt light comes one. Grounds and batt connections are cleaned and look fine. Not sure how to check the fuse block thing connected to the + batt terminal but the fuse in the main fuse box is in tact.

Is this a warning sign for alternator to go?

Most likely, yes. Alternator is going bad.

 

[Gamecocks910]

So just an update on this. took to autozone and the first test came back that battery and alternator were passing the test on the digital tester but then the manager went in and got an analog Schumacher tester and the needle was not getting to the "charging" section. Went home and got readings anywhere from 11.2V to 13.8v and they would fluctuate depending on when I checked. Sometimes it would be fine then an hour later it would read in the 11s.

Thinking shes about to go. My indy mech cant get to it until Monday so hopefully she will last until then!

 

[Patassa]

So just an update on this. took to autozone and the first test came back that battery and alternator were passing the test on the digital tester but then the manager went in and got an analog Schumacher tester and the needle was not getting to the "charging" section. Went home and got readings anywhere from 11.2V to 13.8v and they would fluctuate depending on when I checked. Sometimes it would be fine then an hour later it would read in the 11s.

Thinking shes about to go. My indy mech cant get to it until Monday so hopefully she will last until then!

You could buy a spare battery and just keep it in the vehicle in case the alt gives up between now and then. If you don't end up needing it, you can usually return them. A fresh battery will get you hours down the road with no alternator. Ask me how I know.

 

[D21FJ60]

You could buy a spare battery and just keep it in the vehicle in case the alt gives up between now and then. If you don't end up needing it, you can usually return them. A fresh battery will get you hours down the road with no alternator. Ask me how I know.

This is good to know- i put a reman denso unit in my 100 back in february or march, light came back on beginnig of mauy and its been sitting since.
I have an extra battery from when the old one went out...need to know if its my alternator or what- light is on with 2 good batteries swapped out.

 

[YezusLX]

Mine decided to skip the warning sign procedure and go straight to dead. No lights, no weak starts, nothing. But I was able to pick up one of those H.O.220A from BNR. Rumor has it Uncle Sam's delivery service will drop it off soon. Maybe the 8th? The LX will run off my Sequoia via jumper cables but the moment I remove them it stalls and has no lights. The battery was one of those fancy giant 37Fs from the dealer with a lifetime warranty so once the alternator has been swapped I will be replacing that as well.

 

[Gamecocks910]

You could buy a spare battery and just keep it in the vehicle in case the alt gives up between now and then. If you don't end up needing it, you can usually return them. A fresh battery will get you hours down the road with no alternator. Ask me how I know.

Wanted to close the loop on this thread and I should of listened to @Patassa.

Long story short, alt and battery continued to test "good" and then my daughter decided to come a few weeks early. I hadn't been driving the lx at all during the few weeks I was out on leave since my wife didn't need her car. Decided to fire up the LX and make the dumb decision to take a bunch of crap to the county dump 30 miles away from my house. Alternator symptoms were consistant from before I parked the LX so I thought I was good to good. ANDDDD I was wrong. I get all the way to the dump and 2 miles out, the lx starts chiming, all lights coming on, etc. It literally stalls out as I pull into the landfill.

Had to get it towed to my indy, and $200 for the tow and $500 for the new alternator later we are back baby!

To wrap up, when the battery light comes on and you have a new battery....save yourself some trouble and replace the alternator

Side bar - I sold my daily 2018 King Ranch over a year ago and have been driving the LX daily so I forgot about fancy tech in cars. While I was on leave, I was driving my wifes 2021 cross over SUV for 3 weeks straight....New technology is for the birds. Give me a 100 series that a phone wont connect to 10x out of 10 hahaha. I was considering getting another truck in 6-8 months when the used market gets back to normal and now I don't want to.

 

[D21FJ60]

Give me a 100 series that a phone wont connect to 10x out of 10 hahaha.

Absolutely. My replacement alt should be here monday, can't wait to get back on the road. Can't stand our pilot when loudly starts blaring a random song via bluetooth. The single DIN I put in the 100 can't even connect via cord the first time.

Glad you got it worked out!