Seems like a good idea.

I am already annoyed by the smart charging, I can clearly see, on the voltmeter screen, when the truck is or isn't charging. It's a nearly 2v difference.

I never correlated it to drivetrain performance (my Gen 1 didn't behave as oddly as my Gen 2, despite also having the same system) but since I rely on my truck battery for camping, I didn't like that it wasn't always charging, like older setups did. I feel like sometimes maybe the battery hasn't been charged 100%

 

If you are using an agm battery you need the smart charger otherwise the battery will pop. If you are using a traditional lead acid battery then disconnecting the smart charger would be fine.

 

I KNEW there had to be a reason for that connection. Now I just need to go check which type I have. I'm pretty sure it's AGM. Bummer.

 

Interesting. Everything I’ve seen on here and the Titan Facebook groups seems to indicate the smart charging system doesn’t play nicely with AGM batteries and needs to be disconnected. Not saying you’re wrong, I’m not familiar with the nuances between lead acid and AGM batteries, just that there seems to be conflicting information about this.

 

An AGM charge profile is different from FLA charge profile. An FLA charge profile used on an AGM battery will result in premature decline of the battery. I had that happen to my Odyssey batteries in my UTV. I was able to recondition them fortunately. The Odyssey in my Titan didn't fare so well and had to be replaced just before the 5 year (at that time) warranty expired.

I now use a smart charger with an AGM charge profile to maintain my AGM batteries.

 

As HRTKD states, they are different charge profiles. Will it work yes. But with a traditional charger on an AGM battery it will only charge to approximately 80%.

Ive started numerous times every time this topic comes up, that it’s a bad idea.

Search does AGM battery require a smart charger, answer is yes everywhere.

 

so, reading all the replies, your options are:

a: unplug battery sense wire and truck reads normal voltage and everything on the truck possibly works properly, though you may have to buy a battery more often if you happen to have a specific type of battery in your truck.

b: leave battery sense wire plugged in and deal with odd voltage fluctuations and maybe have weird electrical gremlins but your battery may last a little longer if you have that specific battery.


i unplugged mine and never trouble with the battery or weird electrical gremlins.

though, just to be equal, there are probably tons of people who have not unplugged their sense wire and also have no problems

 

My boat runs 2 batteries, an Optima Marine AGM for the "house" battery, and an Interstate FLA Marine starting battery.
There is no adaptive charging, just a Blue Seas ACR to isolate the house battery during starting and run. When the alternator is charging, both batteries are being charged simultaneously. The ACR doesn't care about battery type.
Both batteries lasted 15 years, they both died in the same boating season.

I've also used AGM red top Optimas in my vehicles in the past. No vehicle had smart charging back then. And those USA made Optima red tops earned a reputation for being the best choice for an upgraded vehicle battery.
Notice I say USA made, because they no longer make their batteries in USA, and the quality has gone way down since.

I don't agree that AGM requires the smart charging. Charge profiles may be different, but the basic LA characteristics are similar enough that they are interchangeable irregardless of charging type. Remember, all vehicles had regular alternator charging when Optima gained its reputation as a great battery.

 

So how does one get the AGM charging profile?

The Titan is set up for a lead acid battery, so regardless of if you leave the smart alternator connection or not, an AGM battery is supposedly not being charged correctly.

 

I believe my original battery said enhanced flooded battery.
This is my second Titan with an AGM in it and no issues and wire still plugged in.

Clint

 

AGM is just a variant of the LA batteries. They are specifically made for use in any vehicle. And have been for decades.

Finding deeper tech information on new Nissan vehicles is damn near impossible, I am curious how some of y'all get your information, or.... disinformation, for that matter

 

the titan doesn't have a smart charger. It a variable voltage control with the only purpose is to save fuel...
here is something to read. Its not the titan but its the same thing...ish

2016 February-March Issue 6 TechTalk Issue

 

Where exactly is this smart charging wire I’ve heard so much about? I’d be nice to know just in case.

 

Found on the negative side cable by the battery post.

 

So what is the intended purpose of the "smart" alternator? Is it simply a fuel savings mechanism? If so, does that mean the alternator creates more drag on the engine when it is actively charging as compared to when it is not charging? So disconnecting the smart alternator cable at battery will effectively force the the alternator to charge 100% of the time the engine is running?

 

That is correct, it’s strictly a fuel saving measure. Theoretically, you might see your fuel economy drop by a fraction of an MPG.

 

I have more experience with LiFePO4 batteries than FLA/AGM. With a LiFePO4 battery, while it can be charged up to 14.6 volts, we typically don't. 14.4 volts is usually enough on the bulk charge and then we fall back to a float charge of 13.6 volts at reduced amps.

I would think that continually charging an FLA battery at 14.5 volts would eventually cook it but the amps to get reduced by the alternator, smart or not. I do agree with you that the alternator has no idea what type of battery is in the truck. Even the smart chargers like the CTEK MUS 4.3 that I use don't know what battery is there. I have to manually pick the right battery.

The newer model Ford Super Duty has a setting in the truck's software for an AGM battery. One of these days I'll get around to changing that setting on my F-350.

 

You’re correct that a floating voltage of 14.5V on a fully charged SLA would overcharge and damage the battery if left long enough, but a vehicle battery is under load while the vehicle is running, so for the alternator to maintain a (nearly) full charge on the battery, it has to run at the power absorption voltage, ~14.5V. On a charger (battery not under load), once the battery is fully charged the voltage should drop to the floating charge level which no longer charges the battery but keeps it from losing charge (if the charger just stopped applying voltage altogether, the battery would slowly drain back through the charger from parasitic draw until physically disconnected).

 

Black, and it fits on a small plastic fitting attached to the earth between the battery and the chassis

 

Ty for info, will look for it!

 

I couldn't get the plug disconnected on my wife's 2013 Infiniti EX37 so I cut the wire with the help of an ASE certified Nissan tech on nicoclub. One time the alternator quit charging and I was going to take it to the dealer to repair but I put a charger set on 25 amps on the battery and I also started the engine trying to figure out why the brake light was also on as well as the battery light and when I disconnected the charger and left to go to the dealer the alternator was charging again. So, I assumed the computer had a brain fart and the charger woke it up. Anyhow, the sensor is disconnected now.

 

So should I disconnect? I don’t know of any problems I’m having and a cheap meter I have plugged into the DC outlet always shows 14v -15v. But I do want my battery at maximum charge at all times givin that I charge batteries for tools off of it regularly. Also I got a little lost reading. Are you guys also saying that a car battery standing alone fully charged would be 14.4-14.6v?

 

Here's a chart..

 

has anyone who disconnected this had trouble with their backup camera system afterwards?? I unplugged mine and now the backup camera won’t turn on. 2018 Pro4x.

 

Nope. Don’t see how it would be related either.

 

Well my battery tested bad at the dealer today, it's the 2nd battery replaced under warranty thankfully but man that Smart charging feature making me think it does shorten battery life. 1st battery lasted a year and this one 2yrs 4 months, I'm used batteries going 3-4yrs in AZ.

 

I am still on the original with my 2017... smart charging plugged in and all...

 

Dang, unicorn battery there

 

I do put my ctek smart charger on it if I don't use the truck for 3 days+. Maybe that helps to keep it going that long.

 

Your experience is why I have several trickle type chargers in use…

They can greatly extend battery life and the alternator life as well…

 

My 2019 pro4x just had it's 3rd battery put in yesterday and it's only got 78k miles on it. I don't know if the Nissan batteries are crap or its the not so smart alternator causing problems but either way something's not right. 😐

 

i have been seeing lots of new vehicles (on the other forums i am part of) have smart charge alternators now. and the common thing i see is people who use an external plug in charger, every once in a while, on the battery get 4+ years out of the batteries.

 

I disconnected mine a few days ago after reading this, and I agree that it makes the truck a lot more pleasurable to drive.