Land Rover LR4 charging profile .. lessons learned

[Mike W]

So I just went through a week of messing with and worrying about my 2013 LR4 for pretty much a misunderstanding about how modern computer controlled alternators seem to work. This is long, but here is the story...

I had a pretty busy week, lots of short drives, the weather had just gotten really cold so more devices pulling amps (heated mirrors, windshield -it has heater lines in the glass, rear glass, side glass, washer nozzles, steering wheel, seats front and rear, rear heating, 17 speakers playing mega-amps of christmas music from sat radio.. this thing uses amps). And I also helped out another driver who had a dead battery and it was really dead.

So I think I drained my precious dual battery setup a lot more than usual. I have a Traxide SC-80 based isolator on a main battery Exide Edge AGM size 49 with 850 CCA, 160 MIN RC at 25A and AUX battery is an Odyssey extreme 34-PC1500.

The Traxide kit crams into a factory battery box that has a few other things in it. Once you move a couple of things around the isolator and breakers and Odyseey AGM fit snuggly and a factory battery tie down works.

So.. anyway. Its very cold and my juice is lower than usual. Now what I normally do is plug into my CTEK 7002 which I keep in the garage and I have an extension plug sticking out of my front grill. It keeps the batteries in great health. But this particular night and a few nights before I hadn't plugged in. So the battery was a bit low, especially for my compulsive self. Probably right around 12.0-12.2v. Now thats not horrible, the deep cycle AGMs will work fine for a long time down there, but like I said.. im a bit compulsive about battery health. (I need to chill the hell out).

So the factory 150 amp alternator is fine, and I don't expect it to charge this setup up very quickly especially on short drives.. so that isn't alarming at all, but I started watching my national luna dual battery monitor for some reason and just started noticing it wasn't ever pushing voltage near 13v. I figured with the battery voltage down the state of charge must be down also and the car should be minimally putting out 13v+.

It wasn't. So with trips coming up, 6+ hours each way and other things, I start to think my alternator took a dump after I jump started that other vehicle. It can apparently happen, and since this event I have purchased a antigravity microstart XP-10 to fit that function so I don't risk messing up anything. So..I start looking for an alternator. Nearest dealer wanted $909 for one. LOL.. rovers. Friend found a new denso, basically same as OEM for $380 after tax. Still a lot, but for a rover.. whatever.

So what comes next ...

So I should have used my fancy IID tool to do some more digging before I did that.. but I didn't, i just freaked out and replaced it. Well... unhooking the power cables did help.. it reset the computer. I don't think changing the alternator changed anything other than a computer reset. So at first I thought.. hey I fixed it! It's charging!

However the charging system on these new rovers is not that simple. We have a Battery Management System (BMS) and a Pulse Width Modulation (PWM) computer controlled alternator, driven by the ECU.

What I didn't know is that the computer will actually lower the voltage below 13v but still pump out amps. In this case it might run at 13.2, 14.7 or 12.2 or 0v. It will still pump out amps and allow the battery to drain at about 2 amps rate.

This is engine startup.. you see the volts kick up, but when it settles it will drop.

So that looked bad to me and thus the change. But if you reset the ECU, it acts perfectly normal for awhile.

But eventually it will switch to "drain" profile or something in between. The lesson learned here is it switches between these modes to .. save fuel or something.. not sure why it wants to let the batteries drain exactly. (Can't i just sit it down and say.. look, dude, LR4... in the winter, in -15F, you get 11mpg anyway.. so STFU and just run the alternator)

So now I know... alternators don't always push 13.2v minimum when the engine runs!

Looking forward to camping again.. need to de-stress now.

 

[Mike W]

Extra engine bay shots.

It is pretty neat.. each battery box is fairly well sealed up, and the clamshell hood seals up against a big seal that goes all the way around the engine bay.

 

[W4P]

Wow!! You need a bunch of beers!!!That's the disadvantage of the glorious connected world! Gone is a set of points,coil,battery and a hammer and bailing wire!!!But you did tough it out and success or failure it's all knowledge!Thanks for sharing!!!

Sent from my Nexus 7 using OB Talk mobile app

 

[SocalPaul]

Nice job.

I'm planning exactly the same (parts on order).

How did you rig up the national luna battery monitor?

 

[Mike W]

Nice job.

I'm planning exactly the same (parts on order).

How did you rig up the national luna battery monitor?

I just recently re-wired that. I ran the wires through the firewall grommet near the brake booster and ran the leads to each battery. That is the only way to get properly accurate readings with loads. I had it wired up to the rear aux distribution block but when you have load it throws off the readings.

With the SC-80, the voltage will pretty much match because of its ability to reverse charge the starter battery from the aux. Its only when you drain the starter battery to 12v (50% remaining charge) that it will isolate and then you will see ~12v (hopefully) on the starter and aux will be lower, down to its cutoff if you have the aux battery cutoff module.

Next project for me is the solar setup.

 

[Fly501]

Mike nice details. Not sure if you still have your LR or if you would be willing to maybe give me your thoughts on the following.

Have a 2016 LR4 with the start stop system on it. I’m struggling at what to do for a dual battery set up. I have found myself researching batteries and everything else under the sun due for the start stop system.

In short the start stop battery is located in the same place that the normal dual battery set up often put in. It uses a 12 V 14AH 200a battery which is essentially a motorcycle battery. My first thought would be to just swap that battery out with something larger (based on available space moving a few bits around).

My second thought is to replace it with a lifepo4 battery. Now I know lifepo4’s don’t like ambient heat, but there is quite a bit going on these days with the packaging, and the BMS’s built in to them.

My goal here is to run an accessory switch controller (trigger6) which will power my LED lights. My thinking is that the LR already has a fancy battery management system on it given the variable voltage alternator in addition to the start stop module. (You can completely disconnect the start stop battery and the vehicle will start and operate just fine, as the start stop system has nothing to do with the primary battery and does not rely on it)

By running the secondary peripheral’s directly off of this battery I’ll still be able to start the car in the morning should I run it out. Running only LEDs I shouldn’t pull a significant amounts of power, and using a lifepo4 will get more capacity for the same physical size limitations. While the truck is running I should have 0 issues, so this is really all driven by wanting power while at camp for flood light at set up, interior, tailgate area, and under awning.

One of my concerns however is whether or not the car is factory system will be able to charge an AGM battery as well as the Lifepo4. My understanding is the lifepo4s BMS will handle the profile for it and just call for juice when needed???

It was also mentioned on another forum that the computer looks for a 14 AH 200 a battery? Not sure how the system would really look for that, but as you point out these days these things are quite advanced.

So my question is simply (haha) do you think it will work?

Now secondary to that, I did purchase a red arc bcdc1240d. My original thought was to pull out the start stop system completely, and use the factory wiring to simply install a secondary battery, the red arc, and tie in solar. But I have come to the understanding removing the start stop module is just not feasible. (I am tempted to just unplug the start/stop module and unhook the battery just to see what happens, but I am certain it will throw codes, and even possible freak the thing out more than a hypochondriac with COVID)

The simplest solution would be to install a big lifepo battery in the back of the vehicle with the redarc and solar, and call it quits. However due to family size the third row seating is a requirement, and thus there is limited space. I do have intentions of installing a fridge in the middle of the second row, but I have now come to the idea that I may be able to use a battery bank system with a built-in pure sign inverter to run the fridge and other peripheral‘s. This reduces the need for a large battery in the engine bay and leads me to the question I am posing. Maybe sell the redarc, buy a lifepo4 for the front, and a battery bank for the rear (charge it off the 12v and 1-2 solar panels? Not sure if I can find a bank that will allow inputs for both at the same time so the redarc or something similar may still be needed for that???) but essentially breaking up the systems. Which is sounding more attractive anyway.

Probably way over thinking this, or missing 1000 other factors, but appreciate any thoughts you have. Found your post after finding some others stating the BMS of the LR will manage to charge multiple batteries on its own without the need for a redarc at all.

 

[REDARC_Ryan]

The simplest solution would be to install a big lifepo battery in the back of the vehicle with the redarc and solar, and call it quits. However due to family size the third row seating is a requirement, and thus there is limited space. I do have intentions of installing a fridge in the middle of the second row, but I have now come to the idea that I may be able to use a battery bank system with a built-in pure sign inverter to run the fridge and other peripheral‘s. This reduces the need for a large battery in the engine bay and leads me to the question I am posing. Maybe sell the redarc, buy a lifepo4 for the front, and a battery bank for the rear (charge it off the 12v and 1-2 solar panels? Not sure if I can find a bank that will allow inputs for both at the same time so the redarc or something similar may still be needed for that???) but essentially breaking up the systems. Which is sounding more attractive anyway.

Probably way over thinking this, or missing 1000 other factors, but appreciate any thoughts you have. Found your post after finding some others stating the BMS of the LR will manage to charge multiple batteries on its own without the need for a redarc at all.

If you're still debating this shoot me an email! We can walk you through a few different scenarios and see what is best for you.

rthurston@redarcelectronics.com

 

[narwhalRL]

If you're still debating this shoot me an email! We can walk you through a few different scenarios and see what is best for you.

rthurston@redarcelectronics.com

This is basically me right now haha.

I have a 2016 LR4 Base w/HD. It is a 5-seater, which makes installing all the equipment behind the 2nd row really easy. Ran power from the engine bay to the 1240D, will install a Lensun 110W flexible solar panel on the hood. AOLithium 100AH battery. 2000W Inverter for when I install a second AOLithium 100Ah battery.

The challenging part is connecting the 4GA wire coming from the engine bay to the red wire of the 1240D. I used a copper butt end splice and crimped.

The only thing I need to decide is the MIDI fuse rating from the start battery to the 1240D. 150A? 200A?

 

[REDARC_Ryan]

If you're still debating this shoot me an email! We can walk you through a few different scenarios and see what is best for you.

rthurston@redarcelectronics.com

This is basically me right now haha.

I have a 2016 LR4 Base w/HD. It is a 5-seater, which makes installing all the equipment behind the 2nd row really easy. Ran power from the engine bay to the 1240D, will install a Lensun 110W flexible solar panel on the hood. AOLithium 100AH battery. 2000W Inverter for when I install a second AOLithium 100Ah battery.

The challenging part is connecting the 4GA wire coming from the engine bay to the red wire of the 1240D. I used a copper butt end splice and crimped.

The only thing I need to decide is the MIDI fuse rating from the start battery to the 1240D. 150A? 200A?

Hey mate,

Sounds like quite the setup! As for the fuse, no need to go that crazy out 60a fuse kit will do the trick.

60A Fuse Kit

The REDARC 60A Fuse Kit is equipped with top quality fuses and fuse holders to fit the cable necessary for the specified current and make a solid connection.

redarcelectronics.com

 

[narwhalRL]

If you're still debating this shoot me an email! We can walk you through a few different scenarios and see what is best for you.

rthurston@redarcelectronics.com

This is basically me right now haha.

I have a 2016 LR4 Base w/HD. It is a 5-seater, which makes installing all the equipment behind the 2nd row really easy. Ran power from the engine bay to the 1240D, will install a Lensun 110W flexible solar panel on the hood. AOLithium 100AH battery. 2000W Inverter for when I install a second AOLithium 100Ah battery.

The challenging part is connecting the 4GA wire coming from the engine bay to the red wire of the 1240D. I used a copper butt end splice and crimped.

The only thing I need to decide is the MIDI fuse rating from the start battery to the 1240D. 150A? 200A?

Hey mate,

Sounds like quite the setup! As for the fuse, no need to go that crazy out 60a fuse kit will do the trick.

60A Fuse Kit

The REDARC 60A Fuse Kit is equipped with top quality fuses and fuse holders to fit the cable necessary for the specified current and make a solid connection.

redarcelectronics.com

Oh perfect, appreciate the info! Thanks so much!

 

[leeloo]

I noticed 2 things on my LR 4 diesel, SDV6, might help others. First 5 minutes after start, specially if it was not driven for a week or more, it does not supply a lot for the 12V cigarette plug. So first 5 min it might supply 50-60 W maximum, after a while it raises the output to the full capacity of the plug, 120w. I think it prioritizes the top up of the main battery and other essential consumers, specially if it is colder.
The second thing, but this might a diesel ting. They do not like at all the start battery lower than nominal. Start becomes sluggish, more turns until it starts, noisier.. . Does not need to be very low for this to occur, lower than 12.6 V it is already visible. Most cars I had, even at 12.2 would be fine..
Also, I read that in general they do not like low voltage, all kinds of weird errors start to show up..
So now, If know I will not drive it for more than week, I hook it up to the home charger.

 

[Fly501]

Just a few extra comments on the original write up. (Nice job by the way)

For those with factory start stop systems it gets a little bit more complex, but theoretically all things work the same and the below should be the same for either.

The BMS, PCM and various ECUs all talk to each other to prioritize power management for the vehicle in relation to battery health. This would include restricting power to non-priority items in situations where voltage is limited, but alos under charging the battery, and even overcharging.

By over charging I mean the alternator will generally always put out less voltage than traditional alternators for the purposes of regenerative braking, or at least the poor man’s version of it. When you let off the gas while moving at relative speed the vehicle will try to capture your forward momentum and turn it into energy. It does this by kicking voltage up to 15v. It’s essentially trying to stuff energy into the battery during these moments.

As the original author implies, when you were at a stoplight the alternator is putting out very low voltage/amps (assuming you’re not calling for a large amount of it) in an effort to lighten the load on the motor and save fuel.

Variable voltage alternators are not new in this regard, but LandRover has certainly stepped up the communication between the rest of the vehicle and the alternator as to when it needs power when it does not in relation to AMP draw, and otherwise maintains a charge profile that is perfectly content with a battery under 13.2v.

The result of this is batteries that are often undercharge relative to what they desire, and are in need of frequent replacement. If you add in that land rover ECUs pull a significant amount of voltage/amps when the truck isn’t running (waking up), and that your ECUs, key fob system, and even air ride system monitor themselves overnight it is not uncommon to get battery warning messages on the dash much more frequently than one might expect. This is especially evident on those weekends where you’re camping or working on your vehicle in and out of it constantly. But even when you were sitting with the vehicle running you may be pulling more amps then are being put back in.

However it is my understanding that you can pull the alternator and send it off to be rebuilt requesting the variable voltage mechanism be removed. (I’m not sure exactly how it works but I’m thinking it’s the mechanical equivalent of an electronic clutch, although it’s probably just diode‘s and resistors) they should result in the alternator putting out a constant traditional voltage, but it will come at a cost of around 1 mile per gallon based on what I was told. This of course will be very dependent on where you live and how much time you spend in stop and go traffic.

For those with start stop systems The ECUs will also prioritize what needs to remain running while in a stop cycle indoor when I start start cycle can be initiated based on roughly 30 different factors. The system he’s designed just like a dual battery set up and that it charges to start stop battery while also charging the primary battery. This is a nice benefit because you can step up the size of the secondary battery or switch to a lithium, and you inherently have a dual battery system

 

[narwhalRL]

I have noticed that my '16 LR consumes way more "power" than my LR3 does when the engine is off. After only two days of camping, I got a low battery alert in the LR4. That with the house lights in camping mode.

On my LR3, I solved my "low power" problems by replacing the stock alternator with a PowerBastards 250A alternator. It delivers 125A at idle and 250 at only 1200 RPM. On the original alternator, I would see huge power drains when running A/C, radio, and headlights. I wish they had an HO alternator option for the LR4!