2013 DMax, so called "Smart Alternator"

Submitted: Sunday, May 04, 2014 at 18:50
ThreadID: 107619 Views:9912 Replies:6 FollowUps:22
This Thread has been Archived
Well it seems that the smart alternator does work to improve fuel economy, Ive been taking note of the fuel economy of our 2013 Auto Dmax for the last 4 months and it has sat steadily at 8.7 l/100kl ( canopy, steel bull bar, winch fitted) No Dual battery system installed !.
After installing the dual battery system ( 110ah AGM battery, dc-dc charger, as advised by an auto elec) the fuel consumption has gone up to 9 l/100kl and according to the volt meter the the alternator is producing 14.2 volts constantly.
I guess that means that the smart alternator is not disengaging as it was supposed to do therefore placing an extra load on the engine, thus increasing the fuel consumption.
Any thoughts ?
Dave



Back Expand Un-Read 0 Moderator

Reply By: Ross M - Sunday, May 04, 2014 at 18:59

Sunday, May 04, 2014 at 18:59
They don't have one.
AnswerID: 531847

Follow Up By: D-Max Dave - Sunday, May 04, 2014 at 19:38

Sunday, May 04, 2014 at 19:38
Service manager at Isuzu dealership says otherwise, he also said that to replace one is $1800.00, that sounds like a lot for an ordinary alternator.
Dave
0
FollowupID: 814967

Follow Up By: Kazza055 - Sunday, May 04, 2014 at 19:41

Sunday, May 04, 2014 at 19:41
Hey Dave, do you want to buy some pills to improve your consumption.

What about a few Hiclones??
0
FollowupID: 814968

Follow Up By: Phil P - Sunday, May 04, 2014 at 20:11

Sunday, May 04, 2014 at 20:11
Wow, $1800 for an alternator. That's almost 5% of the value of a brand new vehicle (assuming the $40k drive away price is still available)

0
FollowupID: 814973

Follow Up By: HKB Electronics - Sunday, May 04, 2014 at 20:25

Sunday, May 04, 2014 at 20:25
Price an OEM alternator, I'll think you'll find their all around that price!

The smart charge function is done by the engine management function and not the alternator, the alternator will be more or less standard except it will have an extra control wire, the Toyota Prado's for instance already have the control wire, it just is not being used as yet.

Leigh

Lifetime Member
My Profile  Send Message

0
FollowupID: 814976

Follow Up By: Ross M - Sunday, May 04, 2014 at 20:27

Sunday, May 04, 2014 at 20:27
Dave
You might be surprised? No one else has found one on their Dmax's.
0
FollowupID: 814979

Follow Up By: D-Max Dave - Sunday, May 04, 2014 at 20:30

Sunday, May 04, 2014 at 20:30
Leigh
That being the case, do i or dont i need to use a dc-dc charger ?
Cheers
Dave
0
FollowupID: 814981

Follow Up By: HKB Electronics - Sunday, May 04, 2014 at 21:20

Sunday, May 04, 2014 at 21:20
Dave,

As far as I'm aware the current DMAX does not have an ECU controlled alternator and doesn't need a DCDC charger or booster diode etc, a simple VSR setup should work well. If you would like to confirm for yourself I would suggest you do as follows:

After car has been garaged overnight, start car wait a minute or so and note the voltage across the cranking battery terminals with engine at 1500RPM, drive car for 30 minutes or so and do same, monitor for a few minutes.

If first reading is around 14.4V and second reading is similar then you have a normal constant voltage alternator setup. If you see the voltage dropping to under 13V you most likely have an ECU controlled alternator.

Lifetime Member
My Profile  Send Message

0
FollowupID: 814994

Follow Up By: Member - Phil G (SA) - Tuesday, May 06, 2014 at 11:44

Tuesday, May 06, 2014 at 11:44
The following was lifted from the TJM site and lists the post 2012 DMax as having a variable voltage alternator
......................................................................
Some vehicles released in late 2010 onwards with common rail diesel and petrol engines have variable voltage alternators that are on the vehicle CANBUS. These alternators vary output based on driving conditions at the time. The range of voltage can be between 12.3V and 15V For this reason, the alternator may not charge a dual or multi auxilary battery bank at all times, and may apply too high a voltage for the auxliary battery chemistry type at other times.

Known vehicles with this style of alternator - Nissan Navara D40, R51 Pathfinder 2011 onwards V6 Diesel only. Hyundai Santa Fe 2010 +, Range Rover 4 2011 +, Ford Ranger 2011 +, Pajero 2012 +, Mazda BT-50 2011 + and Land Rover Disco 4, Isuzu D-Max 2012.
...............................................................................
0
FollowupID: 815151

Follow Up By: Member - Phil G (SA) - Tuesday, May 06, 2014 at 11:58

Tuesday, May 06, 2014 at 11:58
Just read Evaredy's post below, and it looks like TJM might have it wrong.
0
FollowupID: 815152

Reply By: Member - Phil G (SA) - Sunday, May 04, 2014 at 19:51

Sunday, May 04, 2014 at 19:51
I assume your voltmeter is measuring the second battery voltage - so 14.2 is about what you'd expect with a DC-DC charger.
AnswerID: 531850

Follow Up By: HKB Electronics - Sunday, May 04, 2014 at 20:29

Sunday, May 04, 2014 at 20:29
14.2 sounds a little low for a DCDC charger, I would have expected 14.4V to 14.5V.

Maybe volt meter is on the alternator and either the alternator is not ECU controlled or the function has been turned off, if so one would have to wonder why the autoelect installed a DCDC charger when a simple VSR would have performed better?

Leigh

Lifetime Member
My Profile  Send Message

0
FollowupID: 814980

Follow Up By: D-Max Dave - Sunday, May 04, 2014 at 20:40

Sunday, May 04, 2014 at 20:40
i was told I need to use a DC-DC charger because of the so called "Smart Alternator", the voltage is off the alternator, The dc-Dc charger is not a real good one I think, its more of a "battery management control sytem" its an Invertec DC-SW-140.
Its not like the proper Ctek dc-dc charger I have on the camper.
Dave
0
FollowupID: 814984

Follow Up By: Ross M - Sunday, May 04, 2014 at 21:11

Sunday, May 04, 2014 at 21:11
Dave.
When you say, I was told, who is doing the telling?
It all revolves around who knows and says what and understands the variables of the intended usage.

Where is your dual battery?
If close to the main then probably no DCDC required.

I use a dual battery in the tub of a Dmax and with HEAVY wiring it runs at the same voltage as the battery.
I don't even have a VSR, just a simple heavy continuous solenoid.
However, here are situations where a DC/DC unit is a good thing to use, like in a camper where runs are long.

If the batteries get flat a 20amp DC/DC unit running flat out will take a few hours to charge it all.
0
FollowupID: 814991

Follow Up By: HKB Electronics - Sunday, May 04, 2014 at 21:29

Sunday, May 04, 2014 at 21:29
Dave,

The DC-SW-140 is a VSR not a DCDC charger!

Cheers
Leigh

Lifetime Member
My Profile  Send Message

0
FollowupID: 814995

Follow Up By: D-Max Dave - Sunday, May 04, 2014 at 21:45

Sunday, May 04, 2014 at 21:45
Ok, getting a little confused now.
I was told by the service manager at The Isuzu dealership and also an auto electrician.
Battery is in the tub.
Heavy cables used.
The output of the dc-sw-140 with the engine running is the same as the voltage at the main battery (14.2 volts)
If the Dc-sw-140 is a vsr and im getting a 14.2 volt output then it should work ok, right ?, on not.
Dave
0
FollowupID: 814998

Follow Up By: Ross M - Sunday, May 04, 2014 at 22:15

Sunday, May 04, 2014 at 22:15
I have never looked but logic would indicate that
DC is a DC supplied thing, and SW is a switch, and the 140 means that DC SWITCH can handle 140 amps.
0
FollowupID: 815008

Follow Up By: HKB Electronics - Monday, May 05, 2014 at 11:32

Monday, May 05, 2014 at 11:32
Yes Dave,

The setup should work ok as is, no need to change anything.

Cheers
Leigh

Lifetime Member
My Profile  Send Message

0
FollowupID: 815053

Reply By: Member - Andrew L (QLD) - Sunday, May 04, 2014 at 21:22

Sunday, May 04, 2014 at 21:22
"8.7 l/100kl ( canopy, steel bull bar, winch fitted) has gone up to 9 l/100kl "

So to scientifically measure that 0.3L/100km difference over time/distance you have used the same bowser, same ambient and ground temperature, mass, speed average and altitude running to ensure comparison consistency..?

..or are we talking bum dynometer analysis..?
AnswerID: 531864

Follow Up By: D-Max Dave - Sunday, May 04, 2014 at 21:50

Sunday, May 04, 2014 at 21:50
Nothing scientific about it, its based purely on what my fuel economy gauge is telling me, which I know is not 100% accurate, but it did change right after adding the dual battery system !
Dave
0
FollowupID: 815000

Follow Up By: Ross M - Sunday, May 04, 2014 at 22:19

Sunday, May 04, 2014 at 22:19
To take notice of the dash abacus is probably not a goo d method to check things.

I do love the comment from Andrew L " BUM DYNAMOMETER.

If you wear thick nappylike undies that error may vary so it isn't a good method either.
1
FollowupID: 815009

Follow Up By: John and Regina M - Sunday, May 04, 2014 at 22:29

Sunday, May 04, 2014 at 22:29
I like the bum dyno as well.
Nothing scientific or, indeed, accurate about the method used. Trips vary, humidity and temps change, driver moods dictate right foot enthusiasm, traffic lights, wind speed and direction etc.

And yes, the DMax does not yet have a smart (or dumb) alternator.
So the whole concept is moot.
0
FollowupID: 815013

Follow Up By: Member - Rosco from way back - Sunday, May 04, 2014 at 22:30

Sunday, May 04, 2014 at 22:30
LOL A fitting finale to Act 1 of a most interesting discussion.
I await more with baited breath.
0
FollowupID: 815014

Follow Up By: HKB Electronics - Monday, May 05, 2014 at 12:18

Monday, May 05, 2014 at 12:18
Not getting involved as to the test environment, just looking at the simple physics, if you add a dual battery system and use it you have to replace the energy you have used, in this case the energy is supplied by the motor. If you use a 100Ah at 14.4V that's around 1.4Kw you've drawn from the motor and that's not allowing for conversion loses etc.

So yes you will use more fuel. Same as turning off the smart charge function, if you raise the base voltage all the electrical equipment will consume more power and more fuel, you can't have it both ways though, if you need the power you have to burn the fuel.

It is interesting to look into the engine management ECU to see what lengths the car manufacture have gone to improve idle fuel consumption and hence minimise the pollution emissions to meet the standards.

Take the Toyota Prado diesel for example, they use a high compensation alternator to lower the charge voltage to reduce engine load, they have firmware in the engine management system to minimise fuel consumption at idle, the ECU looks at every cylinder as it fires and times the acceleration of the piston stroke and and continually adjusts the fuel flow to each cylinder at idle to balance the power output from each cylinder. Of course once you put the foot down it disregards all that and reverts to look up tables to get the horses going.

Cheers
Leigh

r

Lifetime Member
My Profile  Send Message

0
FollowupID: 815055

Reply By: evaredy - Monday, May 05, 2014 at 12:39

Monday, May 05, 2014 at 12:39
The Dmax does not have a Variable voltage regulator.

I went through all of this with my 2013 Dmax. I wanted to put a 120ah battery in the tub and at the time it was thought that I would need a BCDC 1240-LV because of the alternator.

After some discussion with Redarc and them finally confirming with Isuzu that it is a normal alternator. I was told that I wouldn't need it after all.

I had already purchased the BCDC 1240 I went ahead and had it installed anyway.

I have now also mounted a 150W solar panel on the roof of the canopy and is wired into the BCDC, so the battery is charged when sitting out in the sun. Although I could have done it a bit cheaper, I am happy with this setup.
AnswerID: 531901

Follow Up By: evaredy - Monday, May 05, 2014 at 12:55

Monday, May 05, 2014 at 12:55
I meant to say Variable Voltage Alternator not regulator.

0
FollowupID: 815057

Reply By: Razerback - Monday, May 05, 2014 at 22:42

Monday, May 05, 2014 at 22:42
After the installation Dave you may have also added around 50KG in weight. Weight plays a huge part in your average economy. Off course lots of things will effect the .3 litre variance however adding 50KG will not give you better economy that's for sure. 9L/100km is exceptional economy no matter what, think you are a lucky man.!
AnswerID: 531944

Reply By: D-Max Dave - Tuesday, May 06, 2014 at 12:34

Tuesday, May 06, 2014 at 12:34
Hi All
Thanks for all the comments and advice, here is the reply from Isuzu !

Dear David,
Thank you for your email.
The Isuzu D-MAX does not have a computer controlled alternator – we are unsure why the dealer would have said otherwise.
Additionally, the dual battery system is not recommend or endorsed by IUA.
Thanks and regards,

Customer Relations Coordinator
Isuzu UTE Australia Pty Ltd

Well a lot of you may be saying "I told you so" and others may be suprised, I did really not know what to expect.
As it turns out I think I have installed the appropriate system, more by luck than anything else, I installed what I thought was a DC-DC unit but it turns out to be a VSR which is all I needed.
Again
Thanks
AnswerID: 531962

Sponsored Links

Popular Products (13)