PS - Get over the notion that the ECM is responsible. The BCM is the guilty party, and that's why there isn't a firmware fix and won't ever be. BCM's are part of the security system and are never reprogrammable. So they'd have to replace every BCM on every Armadillo since '17, and QX80's going back even further. That ain't happening over something which can be remedied with a snipped wire.

Apparently my dealer doesn't know about it, which is why my battery wasn't getting charged enough. So replacing the BCM wouldn't make a difference? Sorry if that's a ridiculous question. You mentioned reprogramming the ECM doesn't help, and the BCM isn't reprogrammable, but I wasn't sure about replacing the BCM, maybe if an updated one exists which can better monitor the current sensor? Thanks.

Sounds like maybe there isn't a better replacement BCM, or at least it's not worth battling with the dealer to get one. The current sensor is disconnected and that's good enough. It's just frustrating that the dealer claims to have no idea what I'm talking about with disconnecting the sensor. Can't say I'm surprised though. Thanks again for your help.

You're not getting this, the dealer can't admit they know anything about it. There's no "official" fix and won't ever be, simply because BCM's are expensive stuff and this is an easily-fixed, minor issue that only affects a small percentage of owners. So if you approach Nissan about a BCM, I'm sure the answer you get will be, "Huh?" Like the solution, the problem doesn't officially exist (and it's probably better off that way).

Wow. Crazy stuff. I just can't help but think about all the other owners facing this issue who don't bother to research it, have no idea about it, their dealer has no idea, and they're stuck with a vehicle that won't start. I guess they just sell it and take a loss or something. Doesn't seem right, but that's just how it is I guess. Thanks again for the insight!

The dealer has a perfectly good idea, I assure you. Just not if you call on the phone, because it isn't for public discussion. If you brought your car in for actual diagnosis, you'd get it back fixed with the IPDM "adjusted" or "reconfigured" and no idea what was actually done to it. Most of the Service Advisors don't even know, it's a shop thing that came down to us through Engineering and the DTS's. Since most of the affected cars show up while still under warranty or have aftermarket coverage, the large number of affected owners you're imagining doesn't exist in the real world.

I see. Still crazy though. It's still Nissan's mistake, so I think they should announce the official fix, even if that means they admit they messed up. I just got a $50,000 vehicle that wouldn't start. I don't think I should have to pay for diagnosis to get it "fixed." What a world we live in, eh? Thanks again.

VStar650CL wrote: ↑

Mon Sep 19, 2022 1:53 pm

The dealer has a perfectly good idea, I assure you. Just not if you call on the phone, because it isn't for public discussion. If you brought your car in for actual diagnosis, you'd get it back fixed with the IPDM "adjusted" or "reconfigured" and no idea what was actually done to it. Most of the Service Advisors don't even know, it's a shop thing that came down to us through Engineering and the DTS's. Since most of the affected cars show up while still under warranty or have aftermarket coverage, the large number of affected owners you're imagining doesn't exist in the real world.

i don't think that info got to my dealer. they told me everything was normal. i told them i won't pay for them to guess around, only if they give definitive diagnosis and repair. they accepted my terms and i left without paying.

i came home and 5 mins later my car was fixed.

Yoda's Master wrote: ↑

Mon Sep 19, 2022 7:44 pm

i don't think that info got to my dealer. they told me everything was normal. i told them i won't pay for them to guess around, only if they give definitive diagnosis and repair. they accepted my terms and i left without paying.

i came home and 5 mins later my car was fixed.

The bulk of the problem is pretty much confined to '17-up Armadas and QX80's (and in older times M's), so I'm not surprised if a dealer was reluctant to do it on a different model. Not to say you can't do it yourself if your particular ride has an issue. We're all aware that the "smartwork" can turn into "dumbwork" under a given set of circumstances and driving conditions. But on older Armadas and QX's the culprit is usually a bad current sensor.

Yoda's Master wrote: ↑

Sat May 04, 2019 3:50 pm

madmanpauly wrote: ↑

Fri May 03, 2019 10:43 am

There's a fix for the alternator issue if you are interested. Since the problem is the ECM is controlling the alternator and it doesn't kick on until after 8 miles (as you mentioned), you can disconnect the wire to the alternator and it will always be on. I worked with Jay and was able to disconnect the wire on my 2011 M56 Sport. I did it 2 weeks ago and it is amazing the difference! It feels like it runs better but that may be a placebo effect on me because it is such a relief to confidently start the car each time. I work exactly 7.2 miles from my home so it was always an issue by Wednesday and I charged it over the weekend. Jay's contact source is below, he can help you out but I also put a link to a video that he made about it. I hope this helps!

Video:
https://www.youtube.com/watch?v=P9C5-OkxrJU&t=4s

Jay's website:
http://www.justanswer.com/car/expert-jay1/?rpt=3800

interesting. i have the same problem and thought it was a faulty alternator. replaced it and same thing, no charge.
I just did it to my car and I'll see if it works tomorrow. I have the battery disconnected for now since that stupid vline2 module screwed up my HU settings.

I've had that same exact problem with my 2013 Nissan Quest. The shops test and claim everything is working as it should.
After finding this thread, I asked the shop that currently has my car about disabling this control of charge and he said that although is DOES work to make it start charging the battery any time the engine is running, it also disables the voltage regulator greatly increasing the likelihood of battery damage due to the vehicle overcharging the battery.
Now I'm wondering. Does the mechanic who doesn't work for the dealership have correct information about the voltage regulator also being disabled, or does the voltage regulator continue to limit the charge to the battery after this wire is removed.
Also, does anybody have an image showing where the connector is located and which wire I'd have to remove to get my 2013 Nissan Quest to charge the battery during my barely 8 mile drive between home and work?

You can see your wiring diagram on CHG-19 here. The wire going from pin 76 on the IPDM to pin 5 on the alternator is the offending control wire:
https://www.nicoclub.com/service-manual ... %2FCHG.pdf
The Quest FSM is a bit screwy like the Z manuals, so you need to find the connectors in a different place, they're in the PG section. That seems to be missing in Nico's collection for '11~'13, but fortunately, you can also find the IPDM information in the PCS section here:
https://www.nicoclub.com/service-manual ... %2FPCS.pdf
The connector layout is on PCS-18, and looking down the pin reference to PCS-21, we find the wire should be Gray in color (GR, don't ask me why Nissan doesn't use GY like everybody else). Clipping and capping that Gray wire will put your alternator on internal regulation.

Vis your dealer, the only reason I won't call BS on that explanation is because it's a common misperception among techs which Nissan does nothing to correct. The smart charging is there strictly to save fuel, not to prevent over-charging. Cars ran with internal regulation for years before "smart charging" was even a twinkle in an engineer's eye, and you will not harm your battery by disabling the smartwork. You will prevent harm to your battery from chronic deep-discharge, at a cost of maybe 0.1 mpg on the highway.

Rcmodelr wrote: ↑

Sat Nov 05, 2022 2:24 am

Yoda's Master wrote: ↑

Sat May 04, 2019 3:50 pm

interesting. i have the same problem and thought it was a faulty alternator. replaced it and same thing, no charge.
I just did it to my car and I'll see if it works tomorrow. I have the battery disconnected for now since that stupid vline2 module screwed up my HU settings.

I've had that same exact problem with my 2013 Nissan Quest. The shops test and claim everything is working as it should.
After finding this thread, I asked the shop that currently has my car about disabling this control of charge and he said that although is DOES work to make it start charging the battery any time the engine is running, it also disables the voltage regulator greatly increasing the likelihood of battery damage due to the vehicle overcharging the battery.
Now I'm wondering. Does the mechanic who doesn't work for the dealership have correct information about the voltage regulator also being disabled, or does the voltage regulator continue to limit the charge to the battery after this wire is removed.
Also, does anybody have an image showing where the connector is located and which wire I'd have to remove to get my 2013 Nissan Quest to charge the battery during my barely 8 mile drive between home and work?

That is all
The alternator voltage regulator still outputs at 14.4V MAX, the charging regulator is no longer regulated so instead of charging (or not charging) at low 11 volts (which damages your battery), the battery charges at a healthy 13.something - 14.4 volts. I have no issues and it's been a few years since I've done this, however you NEED to replace your battery AFTER disabling since your existing battery is already shot. If you don't then you'll have a red herring situation where the battery initially lasts longer, but then starts dying again. My M fell victim to the red herring and made me think this was snake oil, but no issues since I replaced the battery. Tested it on my Z and got the exact same scenario.

If you're charging higher then 14.4V or lower than 13V after doing this mod, then go buy a new alternator.

Also, if what the stupid mechanic says it'll kill your battery, then ask yourself why do batteries last years and years on dumb cars without the dumb charging circuit?

Time to find a new mechanic.

Yoda's Master wrote: ↑

Sat Nov 05, 2022 10:37 am

Also, if what the stupid mechanic says it'll kill your battery, then ask yourself why do batteries last years and years on dumb cars without the dumb charging circuit?

Time to find a new mechanic.

Definitely +1 on the "ask yourself", but it's not entirely fair to blame the tech. In some sense Nissan deliberately mis-educates us about that so we won't f___ with it and sever the wrong wire. Least common denominator and all that. Only a tech like me with a ton of electrical experience will know better, it isn't something you'll learn in Nissan Advanced Electrical class.

Good point about red herring syndrome. A smart charger that's gone stupid can deep cycle a battery repeatedly, and just one instance that goes below around 8V can kill as much as 20% of the CCA. So if the battery has gone dead multiple times, replace it out of hand.

VStar650CL wrote: ↑

Sat Nov 05, 2022 11:39 am

Yoda's Master wrote: ↑

Sat Nov 05, 2022 10:37 am

Also, if what the stupid mechanic says it'll kill your battery, then ask yourself why do batteries last years and years on dumb cars without the dumb charging circuit?

Time to find a new mechanic.

Definitely +1 on the "ask yourself", but it's not entirely fair to blame the tech. In some sense Nissan deliberately mis-educates us about that so we won't f___ with it and sever the wrong wire. Least common denominator and all that. Only a tech like me with a ton of electrical experience will know better, it isn't something you'll learn in Nissan Advanced Electrical class.

Good point about red herring syndrome. A smart charger that's gone stupid can deep cycle a battery repeatedly, and just one instance that goes below around 8V can kill as much as 20% of the CCA. So if the battery has gone dead multiple times, replace it out of hand.

I hear ya and it's not meant for everyone, just this one person who lacks common sense to recognize how dumb that sounded.
Do non-Nissan techs get the same Nissan training?

No, Nissan has training facilities all over the place for instructor-led courses using real cars (I usually go to either Dallas or Nashville) but they're strictly for Nissan/Infiniti technicians. They're mostly 1-week courses and there's a required list for each specialty, Electrical, HVAC, Engine, Chassis, etc. The online stuff (there's a crap-ton of that) also requires a Nissan log in and there's a required list. The only "non-Nissan" training required is taking the ASE tests, which are generic for all technicians and brands. When you pass all the ASE's and all the Nissan training, you get your Master Tech plaque.

In the "not for dummies" department, some years back Nissan changed their instructor-led Basic Electrical Course from the normal format (6~8 in the class with 3~4 pairs of "partners") to a "strictly solo" format with the threat of ejection if you helped anybody else. That's because a lot of people who shouldn't be in the same room with electrons were getting through the course on the shoulders of a more-capable partner. In this day and age of LAN's and wire monsters, that was becoming disastrous.

Just another update. I just had my 2019 Armada in because the transmission randomly broke. Didn't shift into reverse without laying on the gas pedal, then jerked back. The dealership said they consulted techline about concern and same issues have been found in other vehicles with replacement of transmission assembly to resolve concern. So it was covered under warranty. Anyway, when I had it in, I told them about the charging concern and this time they recognized the issue and fixed it by "Plugged in battery current sensor and de-pinned connector E13 pin 33 red wire in the IPDM to help battery charge and last longer." So far it's working well. Does anybody know for sure if that is the correct wire? I'm assuming it is, but you never know. Also, I figured I would post it here in case it helps anyone else. Thanks.

Yep, that's the one. We do the fix a lot on '17~'19 Armadas. If you got an RO from us it would say, "reconfigured IPDM", because Field Engineering told us to use that term and not offer details unless the customer asked. But it's the exact same fix as the M's, just a different wire location.

Great to hear! Thanks!!

I’m new here and was hoping a member here could help out the Frontier crowd with this same (variable voltage charging system) VVCS.

I belong to Club Frontier forum and it seems the new 3rd gen (2022-2023) owners are running into a bit of a hiccup in trying to locate the proper wire within the IPDM to disconnect the “not so” smart alternator signal?

I was hoping a member here could shed some light for me as any wiring diagrams members have obtained and cross referenced to the 2nd gen Frontiers do not quite match when it comes to the charging system.

I appreciate any feedback in advance. Thank you

Let me look it up tomorrow when I can access ASIST at the dealership. Many of the new models have "talking" alternators connected to the ECM by a LIN line instead of to the IPDM with a PWM interface, so don't get your hopes up. It isn't possible to modify that setup without lighting the MIL.

VStar650CL wrote: ↑

Wed Apr 05, 2023 6:07 pm

Let me look it up tomorrow when I can access ASIST at the dealership. Many of the new models have "talking" alternators connected to the ECM by a LIN line instead of to the IPDM with a PWM interface, so don't get your hopes up. It isn't possible to modify that setup without lighting the MIL.

Appreciate the effort either way. Look forward to your findings

Okay, bad news first, the alternators on D41's are the LIN type. You can't disconnect the comm line because you'll get Merry Christmas on the dashboard. The good news is, it looks like you can disable the Battery Current Sensor without lighting the MIL. The FSM shows none of the P155x codes causing a MIL or any failsafe behavior, and I imagine the ECM will just regulate according to system voltage if it can't read the current. You can't just disconnect the sensor because that also disables the Battery Temp Sensor, which you still want to work. So try snipping or unpinning the Pink wire at the sensor, that's the battery current signal. You'll get (I think) a P1552 on your scanner, but you should also get fixed alternator regulation. Post back if you try it out.

Hey Vstar650CL, can you also lookup which wire to remove for a 2018 infiniti QX80? I’ve been all over the forums and looked in the diagrams but cannot seem to find it. Would you be able to look it up? I would really appreciate it! My wife is starting to have these issues and the dealership is unaware of anything related to this.

I’m pretty sure it’s at the negative battery terminal sensor but not sure which wire.

You need to talk to a tech at the dealership and not the service advisors. In a perfect world, SA's would know something about cars and serve as a translator between customer-speak and technician-speak, but in the real world the average SA doesn't know any more about your ride than you do. I guarantee you the shop foreman and most of the techs know all about it.

The location for the PWM wire connecting the IPDM to the alternator is identical to what I put up earlier in this thread, the Red wire on pin 33 at the IPDM. You can also disable the Current Sensor by snipping or unpinning the Violet wire on the sensor, but that will cause codes (although not a lit MIL). You're correct that the sensor is on the negative battery terminal/cable.

Ya know, looking back, it wasn't this thread. Give me a few minutes, I'll put up the wire location at the IPDM.

VStar650CL wrote: ↑

Thu Apr 06, 2023 6:30 am

Okay, bad news first, the alternators on D41's are the LIN type. You can't disconnect the comm line because you'll get Merry Christmas on the dashboard. The good news is, it looks like you can disable the Battery Current Sensor without lighting the MIL. The FSM shows none of the P155x codes causing a MIL or any failsafe behavior, and I imagine the ECM will just regulate according to system voltage if it can't read the current. You can't just disconnect the sensor because that also disables the Battery Temp Sensor, which you still want to work. So try snipping or unpinning the Pink wire at the sensor, that's the battery current signal. You'll get (I think) a P1552 on your scanner, but you should also get fixed alternator regulation. Post back if you try it out.

Appreciate the input. It appears the 2020 and up Frontier models use lin bus to communicate between ecm and alternator. It will trip an error to remove this connection.
2020 and above will also store codes without a mil lamp if you disable the current sensor, pink wire you mentioned.
One of the ClubFrontier members did the disconnect of the battery current signal wire, and did get better voltage charging readings after the first ride. No MIL. So we are optimistic so far.

There is no information on how the 2020 and above alternator will work without ecu communication over the lin bus. This is unchartered territory. What do the techs do with customer vehicles that do not operate more than 8 miles per day and get a full charge? There has to be a "work around" for those specific instances? Is this something that can only be programmed/adjusted in Consult only then??

Again, appreciate the help

madmanpauly wrote: ↑

Thu Apr 06, 2023 7:41 am

Hey Vstar650CL, can you also lookup which wire to remove for a 2018 infiniti QX80?

Here you go. The IPDM is located under a cover, in an enclosure directly behind the battery. The beveled corner will be toward the front of the truck at the bottom of the enclosure. E17 will be a black connector, E13 (the one you want) will be white. There's only one all-Red wire on E13, the other red wire is Red/White. Simply snip or unpin the all-Red wire, and tape off the end(s).

GreyFox wrote: ↑

Thu Apr 06, 2023 8:29 am

What do the techs do with customer vehicles that do not operate more than 8 miles per day and get a full charge? There has to be a "work around" for those specific instances? Is this something that can only be programmed/adjusted in Consult only then??

Again, appreciate the help

It isn't something we've come up against with D41's yet, although it's been very common on '17-up Armadas. I really don't see any reason not to snip the Pink sensor wire, which should simply force the ECM to regulate using voltage like a conventional regulator. So it should have the same effect as snipping the wire on a PWM setup, with the exception that you'll get a P155x code. You'll know why that's there, so I'd say just ignore it.

VStar650CL wrote: ↑

Thu Apr 06, 2023 8:43 am

GreyFox wrote: ↑

Thu Apr 06, 2023 8:29 am

What do the techs do with customer vehicles that do not operate more than 8 miles per day and get a full charge? There has to be a "work around" for those specific instances? Is this something that can only be programmed/adjusted in Consult only then??

Again, appreciate the help

It isn't something we've come up against with D41's yet, although it's been very common on '17-up Armadas. I really don't see any reason not to snip the Pink sensor wire, which should simply force the ECM to regulate using voltage like a conventional regulator. So it should have the same effect as snipping the wire on a PWM setup, with the exception that you'll get a P155x code. You'll know why that's there, so I'd say just ignore it.