I had my battery going dead the last few times I've gone to start it. in testing it, turns out the votage regulator is only putting out 13.3v instead of the usual 14.8ish. It's charging, but more of a trickle change instead of the usual quick charge while driving.

Has anyone swapped the Alternator?
First off, how hard is the job? I'm guesing it's tight in there but haven't looked much yet.
Second, is the damn thing made of GOLD? $899 for a new alternator is rediculous! I can get a reman at $200, but I don't know about the quality. I have had issues with reman in the past not lasting and I want to be sure I don't have to do the job more than once.

 

Stock alternator puts out 13 volts or so, I think it's a Toyota thing.

 

Is your car staying on once started? If so, alternator is doing it's job. Assuming that Joker's post is accurate, it may be a battery issue instead as it starts to get a little cooler out there (not sure if that's the case or not where you are).

 

From what I remember mine reads 13 something volts normally, never seen it at 14

 

Interesting. I had the battery tested and read "good but needs charged". They read the alternator at 13.3v and said that was it.

My signs are that the O2 simulators started throwing CEL lights, and the car won't start if left for over 2 days. I may just have to have the dealer test it instead and see what they say

For now I put it on the battery tender for my bike - it's 2amp and charged up the battery fine overnight.

 

Not sure about the O2 simulators issue but if the car isn't starting only after sitting for a few days, then definitely a battery issue...either the battery is shot or something is drawing power from it when the car is off. The alternator keeps the battery charged and electrics running when the motor is on.

Based on what other people have said and this thread (not ISF but should still be relevant), the battery voltage seems in line: https://www.clublexus.com/forums/rx-...g-voltage.html

 

I get 14.0v from mine with a calibrated quality meter. Might have lost a diode in the diode bridge so you're missing a phase. Measure AC voltage across the battery. It should be zero if everything is working right. If it isn't you'll see a measurable AC component to your DC. Not good for anything in the car.

Voltage with car off:


DC Voltage, engine running, lights off.


AC Voltage, engine running, lights off.


DC Voltage, engine running, lights on:

 

Volts should measure 13.9-14.2 with the car running, anything below means faulty alternator.

 

I had the same issue about 2 years ago. Lobux suggested I change out the alt, so I did. It took around 2-1/2 to 3 hrs. Most of the work done from underneath. A set of torx wrenches (not sockets) will be very helpful.

 

Like I said, the car charges around 13.3 volts at temp.

 

With an aftermarket alternator. I'll check again with the engine up to temp, but if it's below 13.8, I'll be surprised.

 

With the obd reader and obd fusion I get 13.1 during normal driving. I know there is some voltage loss so I would bet it just a tad bit higher at the battery and over 3k rpm. The only time I've registered 14 volts was on very cold days which are seldom here in south Florida.

 

I am surprised. Here's the voltage after getting to full operating temperature.



I can only guess they are trying to minimize the battery's charge after it has fully recharged. For 14 volts, or more, you're going to need to pump a lot more current through the battery which has a negative impact on service life.

 

My wireless OBD phone app reads between 13.4 to 13.6 volts.

Lou