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Ok here is the deal. My alternator when out on my frontier last week ( 2007 second generation I guess ). Now I would like to upgrade from my 12v 110amp to a newer model alternator Wich is going to be a 14v 130amp. My question: is the newer alternator model compatible with my truck model? It will be a direct replacement? Or it can't be done?. I really need your guys help here. Thanks
 

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1. Welcome!

2. At some point during the 2nd generation production history, Nissan introduced their hair-brained "Power generation variable voltage control system", which adds a control wire from the engine computer to the alternator. I'm not sure what year this goofy scheme was first introduced on Frontiers, but I think it was some time after the 2007 model year.

This wire allows the engine computer to reduce the alternator's output voltage on demand, in order to slightly improve fuel economy. (Reducing the alternator output voltage also reduces the alternator's mechanical load on the engine, thereby improving fuel economy).

So, even if the newer alternator fits the old mounting brackets, the extra pin in its connector may prevent it from mating with the old engine harness connector. However, if you didn't mind splicing a new-style connector on your harness to mate with the new alternator, it should still work OK without it's "variable voltage control system" connection hooked up to anything. Without it hooked up, the new alternator behaves just like an old one.
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Any alternator ever put on a nissan or any other vehicle is a 14V alternator. The vehicle system is considered 12V but that has no bearing on the alternator. If your OEM alt is not charging at 14V something is wrong with your system. What your saying is you need a higher Amp alternator for whatever reason.
 

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1. Welcome!

2. At some point during the 2nd generation production history, Nissan introduced their hair-brained "Power generation variable voltage control system", which adds a control wire from the engine computer to the alternator. I'm not sure what year this goofy scheme was first introduced on Frontiers, but I think it was some time after the 2007 model year.

This wire allows the engine computer to reduce the alternator's output voltage on demand, in order to slightly improve fuel economy. (Reducing the alternator output voltage also reduces the alternator's mechanical load on the engine, thereby improving fuel economy).

So, even if the newer alternator fits the old mounting brackets, the extra pin in its connector may prevent it from mating with the old engine harness connector. However, if you didn't mind splicing a new-style connector on your harness to mate with the new alternator, it should still work OK without it's "variable voltage control system" connection hooked up to anything. Without it hooked up, the new alternator behaves just like an old one. View attachment 317961
My 2006 has this variable voltage system. When I was having issues with my OE battery I probed my battery terminals to confirm that it was charging only to find that my truck was only putting out 12 volts. Figuring a bad alternator I did some searching and discovered the variable voltage system. Testing the charging systems at random times reveled that it was in fact charging at 14+. My OE battery lasted over 10 years. Though I live in an ideal climate for battery longevity and drive my truck less than the average user, I suspect that in additional to fuel savings the VVS prevents overcharging.
 
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