Battery indicator is on, alternator? (1 Viewer)

[Mike6158]

I was down in Matagorda this weekend. Other than people trying to run their 2WD stock grocery getters on the beach (which was in pitiful shape) it was an uneventful weekend. I decided to take the LC in for a run through the car wash and when I started it the battery indicator light was showing. Dual batteries. Brand new batteries, I replaced a defective main battery right before I went to Big Bend last week. it's not the connections. The posts all have dielectric grease, the connectors are all crimped and soldered.

The LC started fine. I can switch the aux battery in and out with no issues. The "battery gauge" for the dual battery system showed about 12.3V (might've been higher than that. It was well into the green). 207,500 miles on the original alternator. Alternator? Fuse?

 

[TXSunDevil]

What does the battery voltage read while the vehicle is running? If it reads 12.3 I would say alternator. High the high beams and see if the voltage drops then ramps up

 

[vman07]

Any whine from the alt? Whine would increase with RPMs. DENSO remans are on Amazon for like $160, ez job. Drop it out from below, don't disconnect any coolant lines, unecessary.

 

[Spike555]

Why would you shut it off going through the carwash?

Your alternator is dead, the volt meter shows battery voltage not alternator output. The battery light coming on means your alternator is not charging.
It was probably on it's way out and getting water in it from the carwash finished it off.
You can run off of your batteries for as long as you want as long as you keep them charged.

The car runs off the batteries, the alternator keeps the batteries charged, not the other way around.

 

[Mike6158]

What does the battery voltage read while the vehicle is running? If it reads 12.3 I would say alternator. High the high beams and see if the voltage drops then ramps up

I had some time to check it in daylight this evening.

Running - Headlights and fan were off. A fuse marked Main 100A is missing but it's always been missing. 12.42V. When I had the headlights on and the blower fan running it dropped to 12.15V (at idle) and does not ramp up. At no time does the battery symbol lamp go out. Time for that alternator upgrade I've been wanting?

 

[Mike6158]

Any whine from the alt? Whine would increase with RPMs. DENSO remans are on Amazon for like $160, ez job. Drop it out from below, don't disconnect any coolant lines, unecessary.

Nope. None at all.

 

[Mike6158]

Why would you shut it off going through the carwash?

Your alternator is dead, the volt meter shows battery voltage not alternator output. The battery light coming on means your alternator is not charging.
It was probably on it's way out and getting water in it from the carwash finished it off.
You can run off of your batteries for as long as you want as long as you keep them charged.

The car runs off the batteries, the alternator keeps the batteries charged, not the other way around.

"I decided to take the LC in for a run through the car wash and when I started it the battery indicator light was showing."

Breaking this down

1- I decided to take the LC in for a run through the car wash
2- When I started it, the battery indicator was showing. This was starting it BEFORE i left for the car wash.
3- I never made it to the car wash or even out of my driveway.

I probably could have driven the 12 mile round trip and had plenty of battery left.

This -> Your alternator is dead, the volt meter shows battery voltage not alternator output. The battery light coming on means your alternator is not charging.

Very helpful to know. I wasn't sure if it was a voltage trigger (which wouldn't make sense because there is a volt meter for that reading) or a current trigger. Now I know. Gracias

I've been expecting to to go. I think it's weak but not gone.

 

[TXSunDevil]

If I were you I would go get the new alternator.

 

[Spike555]

"I decided to take the LC in for a run through the car wash and when I started it the battery indicator light was showing."

Breaking this down

1- I decided to take the LC in for a run through the car wash
2- When I started it, the battery indicator was showing. This was starting it BEFORE i left for the car wash.
3- I never made it to the car wash or even out of my driveway.

I probably could have driven the 12 mile round trip and had plenty of battery left.

This -> Your alternator is dead, the volt meter shows battery voltage not alternator output. The battery light coming on means your alternator is not charging.

Very helpful to know. I wasn't sure if it was a voltage trigger (which wouldn't make sense because there is a volt meter for that reading) or a current trigger. Now I know. Gracias

I've been expecting to to go. I think it's weak but not gone.

Thank you. I misread/understood what you wrote.

 

[Mike6158]

If I were you I would go get the new alternator.

I think I'm going to go for an upgrade while I'm at it. Which one? I don't know yet, if any. All three are pricey.

2000 Toyota Landcruiser 4.7L V8 2UZ-FE High Output Alternators

180A, 250A, or 270A?

270A is probably a no. For one thing I don't know if the cable from the alternator to the battery can even handle that kind of amperage. I wish they made something in the 225A range.

The idle and hot idle amperage is what I'm interested in. With the air compressor, ham radio, refrigerator, aux lighting (future), winch (future), etc... it would be nice to have 180A or more of current available at idle.

Not an easy decision...

Thank you. I misread/understood what you wrote.

No worries. My attempt at humor probably didn't play well in text.

 

[vman07]

You can get a stock Denso reman for $130 that gives you 130 amps. You should estimate a draw for all of those circuits you plan to run.

I pull pretty often in my little 90 4runner, that alt. puts out like 80 amps max, never had an issue with power delivery while winching. A healthy battery with a bunch of amp hours is going to be more important than a big numbers alternator. Just my two pennies...

https://www.google.com/url?sa=t&sou...FjADegQIBBAB&usg=AOvVaw0EbzrdKQnIor4NuLP8K9pX

 

[Mike6158]

I've got a pair of healthy Interstate AGM batteries. 810 CCA (1,200 Cranking Amps) and 715 CCA (895 cranking Amps). One of the reasons I still haven't pulled the trigger on the higher output alternators is the cost and the people in my head can't make up their mind

Here's how the argument in my head goes-

The thing is, you listed 80A max and 130A. That's revved up, not idling.

Ok... so how often do you think you'll need 130A of alternator output while idling

hell I don't know... I don't even know if I need 130A total with it revved up much less idling.

Ok so why would you spend $400 on an alternator when you can get a reman for $130

Not a fan of reman anything... unless I reman it. Might just be the voltage regulator but it might not.

Ok so why would you spend $400 on an alternator. The stock alternator went over 200k miles... it's not $400...



It's very confusing in there.

 

[Spike555]

DO NOT buy a Green Machine alternator, they are junk.
If you go big amps you will need bing amps battery cables.
Running two batteries stock alternator should be plenty.

 

[Mike6158]

DO NOT buy a Green Machine alternator, they are junk.
If you go big amps you will need bing amps battery cables.
Running two batteries stock alternator should be plenty.

I've been looking at DC Power Engineering

Specifically this one:

180 Amp HP High Output Alternator - 4.7L V8 2UZ-FE - 2000 - Landcruiser - Toyota - HP Series Alternators - High Output Alternators

Basically it's $500.00 and I'd have to upsize the cabling. Plus it's 1-2 weeks delivery.

I'm going to go with a stock alternator. I can't rationalize the added amperage no matter how hard I try. "I want" is getting it's a** kicked by $500 and no real reason to spend that kind of money. Dammit... the adult neurons won again... Thanks for the help...

 

[Spike555]

I've been looking at DC Power Engineering

Specifically this one:

180 Amp HP High Output Alternator - 4.7L V8 2UZ-FE - 2000 - Landcruiser - Toyota - HP Series Alternators - High Output Alternators

Basically it's $500.00 and I'd have to upsize the cabling. Plus it's 1-2 weeks delivery.

I'm going to go with a stock alternator. I can't rationalize the added amperage no matter how hard I try. "I want" is getting it's a** kicked by $500 and no real reason to spend that kind of money. Dammit... the adult neurons won again... Thanks for the help...

That's the same place that makes the Green machine alternator.
You can take your's to a electrical shop and they can turn up the amps for you when they rebuild it, they won't go crazy but you can get 150amps out of it.
I bought mine off of Amazon, Denso factory reman. It was $198 if I remember right, it was 2yrs ago.

 

[Mike6158]

The new alternator (not the DC Power alternator, one from Amazon) is installed and it's working like a charm. I found a YT video that showed going in from the bottom on a 2004. I couldn't use that method on my 2000. I just followed the service manual, pulled the radiator, and went in from the top. I pulled the pulley off of the PS pump so the alternator would come out. After that there wasn't much too it. It's easy to put the serpentine belt on when all that other stuff is out of the way

I think the old alternator has been trying to tell me it was going out. The voltage reading is higher than it used to be. More like what it was when I bought the LC