2006 Range Rover sport. Alternator wasn’t putting out proper voltage only 13v. I had the alternator built. Reinstalled the alternator now I am getting anywhere between 12.1 and13volts. Is there anythig else that might be limiting the output. I tested with a volt meter at the battery and confirmed with my gap tool. Thanks. Phil

 

The way to test an alt:

turn on everything electric with vehicle running. Bring to 2k rpms, test voltage at battery if close to 12 or below, bad alt.

 

With a rebuilt alternator they normally only change regulator and brushes but not the windings - so you are better off with a Denso replacement. Alternators should put out around 14+ volts on startup.

 

Aj am taking it over to the rebuilder tomorrow. Hopefully they can sort it out. They did our lr3 alternator and it come back better than new. Phil

 

Well the alternator is dead again. I replaced the battery today. The last battery was just three months old. It tested bad. The alternator shop thinks that the bad battery may be frying the regulators. I am willing to give it one more shot and if this doesn’t work I may just push it into the San Diego bay. Phil

 

So I really am not commenting on your specific conditions because it's possible that a bad cell in the battery caused the alternator to overwork and burned it out. I just don't know.

But I did want to add, that my alternator started to smell like burning wiring insulation and made a tell tale hum/noise. That, in conjunction with the battery light coming on, was my indication that my alternator was toast. I did a few searches for new ones but they are pretty spendy and I debated back and forth about a used unit and I read nothing but horror stories concerning rebuilt units from the auto parts stores so I decided to buy a rebuild kit which consisted of a new rectifier, brushes, and voltage regulator. I have to say it was a neat little exercise tearing the old one apart. The rectifier is permanently attached so once you cut it free you are committed. It was pretty easy, about 30 minutes and about $80 and everything has been swell since I did it (about a month ago).

I figured I'd add this onto your thread in case anyone was curious about options when their alternator goes south. Good luck with yours.

 

Well, that stinks. 4th time the alternator was at the shop. Put in yet another new regulator. Got home, installed and (drum roll) nothing. It isn’t putting out anything. Voltage tested with a volt meter at the battery and with the gap tool both confirm no juice from the alternator. I am stumped. I need to check the plug on the truck to make sure all is in order and the receptical on the regulator. Next I am going to try a new alternator. On the positive side I did buy a new $220 battery. Phil

 

Maybe time to change to another workshop

 

I ran down to the wrecking yard at lunch and picked up an alternator out of a wreck. $50, we will see if it is worth $50 when I get home tonight and install it. I must say that the shop has been pretty nice about redoing the alternator. Not so nice as to offer to do the labor on the install/destall......the guy asked me today, what I needed to make me happy. I appreciate his customer service. It is really a mystery. Wish me luck Phil

 

...you get what you pay for.