OK, I think my alternator is dead and I have a couple questions.

A.) What tool is best to diagnose whether my problem is a bad battery, a bad alternator, or a bad voltage regulator? Will a battery load tester do?

B.) Is the voltage regulator something that can be replaced without replacing the alternator?

C.) What are the tools I should be sure to have when tackling the replacement itself?

D.) Is there any other part that I really, really, REALLY SHOULD change at the same time as the alternator? My budget is very limited, so I want to keep this to NECESSARY parts replacement.

E.) I have the factory service manual and the Haynes. Anyone give me any general advice not found in those books?

F.) Is there anything I forgot to ask about?

Thanks everyone. I appreciate this. I can't afford to pay to have this done, so all your help will really be worth a lot to me.

Hal

 

Anyone? Before I buy an alternator, I was hoping someone could tell me how to at least test it to make sure I need one.

Thanks

 

Take it to autozone or advance auto parts and they check it all for free..

 

How did you diagnose that the alternator was dead? The battery light should have come on which indicates the alternator isn't charging the battery like it should. To me that would most likely tell me the alternator is dying. But if the light didn't come on, maybe the battery needs replacing. Did the battery light come on while driving?

 

Actually, the ABS and Airbag lights came on. I've recharged the battery to 100%, so I'm going to drive it around the neighborhood and see what happens.

 

jayanth is right, this is your best bet to diagnose in this case. I believe the voltage regulator is integrated into the alternator itself, not positive though.

 

To check if your alternator is dead start the car and pull the + cable off the battery. If your car continues to run then your alternator should be ok since the alternator is powering everything. Go to Autozone to get your battery tested. If you do decide to get a new alternator you can get a remanufactured one to save money or you can upgrade to an alternator with more amps.
http://forums.maxima.org/showthread....GLE+alternator
-hype

 

Well, I drove it around for about 15 or 20 minutes with the A/C on high, the headlights on, the radio loud and the rear defogger on. When I pulled in the driveway, I hooked the battery up to the charger (the only tool I have right now to tell me anything about it), it was about $0-50% drained. And it took a little bit to turn over and start, which it didn't have trouble with on the first start before my drive.

No dummy lights, no symptoms. Maybe a little bit of dimming on the dash lights and clock, but that may have been psychological.

From the info I have, there's no way to tell whether the battery drained because it can't hold a charge or because the alternator's not recharging it, is there?

Hal

 

Take the battery out of the equation and you'll know. 5 minutes should be enough to find out if it's the alternator or not, but if it isn't don't go driving around like that because it strains the alternator.
-hype

 

Well, first off, I found several mentions using the search function that that's a BAD idea.

I did do it, though, by accident, before I knew I could fry my ECU. The car was running and I was going to take the battery out to charge it and I just pulled the negative cable without thinking. The car died instantly.

Hal

 

The regulator can be replaced alone but the nissan guys don't do it, Any of the local mechanics can do it for you, you can save 100's.

 

I just drove 3 miles with a new, fresh battery and it dpleted 25% of the battery's power. I'd say that's good evidence that it's not the battery.

Hal

 

Sorry to point you to a bad solution I learned in the field and obviously to those who don't know better it's a common practice. Makes sense from the electrical point of view though.
-hype

 

No... What you are saying is correct. You just pull the negative off. It can't fry your ecu.. Anyone that seems to think it can is smoking crack (i mean come on that makes no sense why even).. Now if you are so stupid as to take the positive off and touch it to your car then you might have a dead ecu.. By short the alternator system but this is only if your car continues to run..

I mean I feel sorry for the poor sap that did not tighten one of his cables on his battery and it giggled loose (or lost connection) while driving.. Man that poor bastered (probably 25% of us) just lost his ECU.. Stupid!

 

Well at least you tried not to be insulting.

http://forums.maxima.org/showthread....est+alternator

I'll trust anything out of Daniel B Martin's book before yours. He's such a crackhead. Thanks for trying to help.

 

Bump. Still looking for advice from anyone who has changed an alternator. Things to look out for, tools to have, steps that are much easier with a friend. Stuff like that.

Thanks!

 

It is not to bad to change it out.. But the one bolt that is on the lower side there is no easy way to get to. I had to use a really really long exstension on my socket wrench like 1.5 feet long.
If you are looking for exact instructions..
Take of the belt.
Remove the bolt you can get to from up top and the bracket it is attached to..
Remove the lower bolt,.
Wiggle the damn thing for 5 min till comes free.
Take to autozone to ensure it is the problem..
Install in reverse order your new part.
Takes 1 hour.

 

Thanks for the advice. Anyone have any more?

 

Yes, disconnecting the battery while running is not a conclusive test and could also fry your ECM. Assuming the alternator is charging, the voltage regulator could spike and send 16+ volts through your ECM when the terminal is disconnected. Plus, depending on the electrical load it could stall anyway - regardless if the alternator is good or not.

The first thing to do it make sure you have a good battery. Either by charging up the battery you have and load testing it afterwards (a battery must be fully charged - that's 12.6 volts flat to load test), or replacing it with a new one. Sometimes a battery will "short out" across the terminals inside the top cover and the alternator wont charge at all as a result. After that you can test the alternator voltage - should be over 14.1 or so and under 15.5. Actually, anything over 15 I would question.