I swear I looked for a similar post. I did find a couple but they just weren't what I was looking for. I have a 2002 Maxima and I got the alternator replaced with a new alternator because it wasn't charging my battery. Then 6 months later my battery dies again, which is 2 weeks ago. I think it's the battery because it was an old battery so I got a new battery. Still the same problem so now I think it's my alternator. Well I did replace the harness before I took the alternator out but I just took the alternator out and I took it to Napa Auto parts and had them bench test it and they said that it is in perfect working condition. So I'm wondering if anybody knows how I should go about troubleshooting this cuz I've already put the alternator back in my car and it's all put back together. t's just still not charging. All the bolts are tightened and everything I just don't really 100% understand all of this stuff. Does anybody know which fuses could blow that would stop the alternator from charging? What about all the grounds and the fusible links I don't really understand these. there's a fusible link underneath the battery. It looks good I cleaned it off with a wire brush. so it looks good but I just I don't know. I do have a multimeter I just don't really know what to do and I'm hoping maybe somebody could just help me. Thank you.

 

What voltage are you getting at idle with this alternator in the car idling? If you put a voltmeter on the battery it should be 13.4-14.5ish, if its 12.2v or something it's not charging. I would start there before chasing your tail, I was a mechanic for 10yrs and worked in a garage that used mainly Napa parts and literally almost every Mazda MPV or Ford Escape reman alternator we put in came back 3-6 months later not charging to the point where it was comical, reman stuff isn't always good out of the box. There is this thread from 2014 below but it was the alternator itself as well

https://maxima.org/forums/5th-genera...-charging.html


Also worth reading the below

https://www.justanswer.com/car/jkua5...an-maxima.htmlWas the alternator harness brand new that you swapped out and why did you swap it out? The only other thing i've see in my time was years back I was working on a '94 VW Golf where it wasn't charging even with a reman alternator and Partsource tested the alt as for sure good, I traced the wiring harness and the exciter wire that tells the alternator to charge the battery was broken near the firewall. Fixed the wire and all was good.

Start by checking your idle voltage and check the fusible link connection and fuse #70 and #30 then go from there.

This thread is for 4th gens but has good diagnosis instructions as well

https://maxima.org/forums/4th-genera...w-battery.html

 

​​​​​Finally the weekend. I am going to run through everything you said to do and update once finished. Thank you for your time.

 

When I took my car to Napa Auto parts to have them test the newly installed alternator. They had a device and tested it and said "your alternator bad". Well. Yeah. That's just what I told him. So I went home and took the alternator out and brought it back to Napa to have it bench tested. They then said that the alternator is fully functional. When I use a voltmeter on the battery without the car running it is 12.6v. when I turn the car on and test again. It is still 12.6v. The alternator belt is brand new, I just replaced it. It's very snug. So no slipping. Fuses now. Thank you.

 

This may you sound like a dumb question I have googled it and I can't find the answer so I don't know if anybody else has asked this question. How can I figure out what number the fuses are. I found a few diagrams on Google but they don't really match my fuses.

 

ther alternator fuse is the biggest one, right at the battery, 120 I believe.

 

Sounds like if you didn't understand the charging system you should've removed the wiring harness at all. Please grab a schematic and check point to point. First start with your fusible links first. Ensure that the Alternator has it's isolated power wire as well and check that the 3 pin connector is fully engaging and the pins are in clean condition. It may be possible to perform a continuity on the 3-pin connector. You can't do this without a schematic unless you know this system inside out. Make sure your engine bond wire & ground wire is clean and in good condition.