[AnimatedMechanic]

Hey guys, a few days ago my 2nd Gen battery died. I thought it was because the door lights were on after it was left ajar, so I charged it, hooked it back up, started it and then took a voltometer to it, and surprisingly, it wasn't getting any charge from the alternator (read at 11.9 volts). So I swapped it out with another one, and then another one, and then one more, but I got the same reading. I realized then that only one alternator was truly dead because all of the dash lights were on. Then I checked for any shorts/grounds with a test light and found them to be at the lights and radio. I pulled the fuses out (radio no. 1 under the hood and the two 7.5's inside) and then started the car. It did charge for that night (13.5), though I still unplugged the battery. But then the next day, I started it again and checked it, and NO CHARGE. I was getting really frustrated at the car as it is my daily driver. There are no shorts/grounds left and the battery still will not charge. I will note though that when the key is in the ignition and on acc or "on", the short light tester glows very brightly. Is this normal? And does anyone have suggestions to my problem? Thank you in advance.

 

[Doctor J]

Just brainstorming:
alternator fuse (80 A) connections;
bad terminals inside the 3 pin plug on the alternator (too much dielectric grease perhaps?)
alternator bench test (in Autozone?)
Source of your replacement alternators?
If there is a short in headlight circuit the lights will be always on (Toyota design)

 

[AnimatedMechanic]

Checked all of that, it's none of those things.

 

[Gazelle]

Check the alternator rectifiers, mine has failed twice, the rectifier block is commonly available and any good auto electric place can check it. The regulator can fail also. Brushes?

 

[white90dx]

Since you have checked the 'easy' stuff, I would guess weak parts in the alternator. Brushes, rectifier, regulator, etc. Lower load = enough charging, higher load = no charging.

Rebuild or replace the alternator.

-Charlie

edit: Re-read... you've tried more than one alternator?

 

[AnimatedMechanic]

Rectifiers? And yes, I tried (edit) 3.

 

[AnimatedMechanic]

So more tests were ran on 3 alternators and well, two of them weren't putting out any energy. The hard part is though that only one of them showed the 3 dash lights of doom so I am assuming that the other 2 are working. Could this be cause by bad connections/loose wiring? Ignition switch problems?

 

[Doctor J]

I would recommend taking the alternator to the store such as Autozone for free bench testing! If it passes:

With engine off, unplug 3 pin round connector from the alternator;
locate "S" and "ignition" terminal on it
turn ignition on but DO NOT start the engine
You should have a batttery voltage present on these terminals, if not, repair wires.
If voltage is present, plug the connector in, start the engine and measure a voltage drop between "B+" terminal of the alternator and battery positive post.
If more then 0.2 volts, check the wire and 80 amp fuse connectors for corrosion

 

[TOYOPARTSMAN]

Have you considered an OEM alternator?

 

[Guest]

Checked the ALT-S fuse?

 

[Doctor J]

^ Engine fuse, 10A ??

 

[AnimatedMechanic]

Ok guys so the alternators were tested today and ALL 3 failed. The first one which was in the car originally passed everything except for the L-circuit test. The 2nd one which came from the old Camry which I was sure was working failed the light circuit test. And the 3rd one which gave me the 3 dash lights of course failed the DC Voltage test. Could something be killing my alternators in my car? This is becoming extremely frustrating.

 

[Doctor J]

Original voltage regulators could be failing due to the age. In theory a short in the L circuit between the alternator and 7.5 A charge fuse can kill the regulator

 

[AnimatedMechanic]

ok I see. Where do you think the short would be? Dash?

 

[Doctor J]

The short can be between the alternator and fuse box.
But, like I said, the original regulators are failing because of their age; on my rebuild alternator put in 2005 the regulator died in 2006. Installing of freshly produced regulator fixed the problem. Most rebuild alternators is painted junk with new brushes and bearings installed!! they still have original diodes and regulators with low output at high temperature and intermittent failures.

 

[AnimatedMechanic]

ok. And wow thanks for sharing that I did not know that. The first one I had hesitations about since it was recently replaced with a rebuilt but I did not know that most of them are like that.

 

[joeycamry32]

In my pursuit of a custom high output alternator to support a power drain of larger stereo on my 2nd gen, I can't help but relate to going through a few alternators which would failed after short periods of time.

The pattern of problems I had were solved by the purchase of a refurbished stock alternator from a dealership, maybe $200-$300 about 6 yrs ago. I would keep this one on hand. Once the custom alternators would die after a few months, I'd put back in the refurb stock alternator which worked great and was reliable, but only output a max of 70-75A.

Finally, after about a year, I found a great custom alternator builder and now have a modified (Celica I think?) alternator with max 140-150A output, which has lasted me for the last 6 yrs so far and still works great.

The main hassle to me was without a good alternator, the car wouldn't run for very long and it became very frustrating very quickly to have an expensive custom build alternator die when a "new" stock refurb from the dealership worked great, just had a low amperage output.

In relation to your situation, paying for the more expensive refurb stock alternator from the dealership ended up saving me a lot of headaches throughout the process of using custom built alternators of which I had two die after 3-4 months.

The upside is in the process there is an opportunity to learn a lot about alternators! Hope the experience might help a bit. Good luck!

 

[Doctor J]

The quality rebuild alternator has original housing, stator and armature.
The pulley, bearings, diode assembly, regulator and brushes should be new, not "inspected one";
Many people are "hunting" for new regulators and diode assemblies on the junk jards leaving alone everything else

 

[AnimatedMechanic]

So another update, I bought another alternator (remanufactured) and decided to test it before I put it on the car. Lo and behold, it FAILED. Same failure (L-circuit). When it was unplugged, we discovered that the L circuit connector was a bit melted. So one more is coming in tomorrow. Could the tester be frying these things? Or am I having really tough luck with these things?

 

[Doctor J]

What kind of tester is it? The one in the store should not harm the alternator