[ST391GQ]

Gidday Folks,
Have a 2018 Suzuki Grand Vitara sport and am trying to find out if these have a smart alternater ....and can they be turned of from being such and back to being a normal alternator.
It pissed me off when in a real heavy rainstorm last week ...with wipers flat chat, and demisters on with parkers and bulbar fog lights on (LED )...no headlights on tho....and slowing down to go around a roundabout...the wipers slowed too...and then sped up when speeding up WTF ???
Not bad for a 150 amp alternater hey...well at least that's what the book says it has...
I know that Ford Rangers....most holdens and a fair few other brands can have these turned off through hooking up the software and unticking a box or sumthin ...so hoping this car is the same.
Any ideas ???

Cheers Keith

[fordem]

Suzuki started using smart alternators back in 2005 on the JB series Grand Vitaras, so I think it's safe to say your 2018 will also have one - I have no idea if they can be disabled, I've never needed to find out.

[Gwagensteve]

And I’m not sure why the operation of one would appreciably affect wiper speed.

[gbcrown]

I would check the battery.
Shouldn't this be covered by warranty? 2018?

[ST391GQ]

gbcrown wrote:

I would check the battery.
Shouldn't this be covered by warranty? 2018?

Battery checks fine....had to auto lecky today.....and yes ...it is covered by warranty. Spoke to dealer today.....and he has had one other a couple of years ago that needed a tweak in the software.....but also took on board that I wanted the so called smart feature deleted so it would perform like a bloody alternater should .....not just cut voltage when it feels like it to save a poofteenth in fuel usage. I have always felt that the lights could be brighter at times....and the lightbar that has been fitted doesn't seem as bright (the same type ) as the one on my 97 Patrol....but this also comes and goes too. Bloody good thing I don't tow a van with it ...the bloody van battery would never get charged properly.
I have checked the voltage myself at the battery after starting it and a few minutes later....and it checks out fine 14.2.....but a while later it has dropped to 13.1 ...and doesn't go up much with the lights on.....and then a while later ...it is back up to 14.2...which is pretty much exactly what a smart alternater does.....and is why folks who tow vans go crook about the batteries not charging....until the dealer hooks up the gear and turns the smart function off...and then things get normal.
I really would like to know if anyone here has had this problem ....and had the smart function turned off...as I reckon there is nuthin actually wrong with the unit itself .....just the controlling of it.

Cheers Keith

[fordem]

So - what did the dealer say - can he "delete" it?

I have two vehicles with "smart" alternators, one of them being a 2005 JB series GV - which is equipped with a digital volt meter, so I can see the variations as I drive, and they do vary in a manner similar to what you describe - but - no I have no issues with wiper speed variations, or light brightness variations, on either vehicle, and don't see why you should, assuming the installation of any accessory lights has been correctly done, which on a GV means NOT directly to the battery.

Suzuki has a current monitor built into the main fuse panel which the ECU uses to determine current draw and adjusts the alternator output appropriately - connecting accessories directly to the battery bypasses this and can result in the alternator not outputting enough current to supply the required demand.

LED light bars are "current limited" and don't care that much about voltage variations, check the spec. on the ones you have you'll see an input range of maybe 10~30V - you're not going to see any variations in brightness across that range, but, if you put an amp meter in line, you'll be able to watch the supply current increase as the supply voltage decreases (and vice versa), as the driver compensates - any decreased brightness is either imaginary or a manufacturers variation, and given the quality control of the average light bar manufacturer, more than likely the latter.

As to the "van charging issues" - the average "van" system is incorrectly setup, and that is why there are so many issues. The "van" should be using a deep cycle battery, which requires a different charge regime to a cranking/starting battery - parallel them at your own risk - set it up properly, with a DC-DC charger, fed downstream of the current sense and the smart alternator will compensate for the required charge current. Somebody is now going to come along and say that they've been running their van with a simple voltage sensing relay and it works - well - good for you, you were lucky, not everybody is.

[ZUZUKI]

A 'Smart' alternator, is actually a dumb alternator, but being controlled by a smarter ECU.
As has been mentioned, very unlikely to be the cause of your wiper issue.
They are not to be feared & if all is operating as it should, really only a good thing that is working away in the background saving you money, by not wasting fuel.
As in, do you understand the drag on the drive belt it takes to pump out 150A at 14.2V? (150A seems high, BTW) - huge.

A 'smart alternator system' only produces enough A & V to take care of the electrical loads within the vehicle.
At cruise, with everything off, the car would use something like 35-40A to run - why does the Alt. need to produce 100 or 120A?.
When you turn on the heater fan, headlights, wipers, the Alt. output is upped by the ECU to cope with those loads so as not to drain the battery.

The issue with some cars (like the Ranger) is that the ECU has the ability to switch the Alt. off completely - effectively the Alt. is acting as an idler pulley & the car is draining the battery until a preset V level is reached & then the Alt. is switched back on again. This is the function that can be altered by a Ford dealer, but it then still acts like your 'smart' Alt.

You most likely have a loose battery terminal, poor earth in the wiper circuit or other fault not related to the Alt.

And Yes, I'll chime in on the "Van" issues, with 'It depends on distance from Alt. to van battery. van battery 'type', tow vehicle charge rate' - a VSR can & does work in the right situation, many people don't understand the 'right situation' though.
A DC-DC is a catch all 'fix' that might not be the best answer, but will work, of a fashion.

Rgs, Michael

[fordem]

ZUZUKI wrote:

A 'smart alternator system' only produces enough A & V to take care of the electrical loads within the vehicle.
At cruise, with everything off, the car would use something like 35-40A to run - why does the Alt. need to produce 100 or 120A?.
When you turn on the heater fan, headlights, wipers, the Alt. output is upped by the ECU to cope with those loads so as not to drain the battery.

What you've just done is describe the functioning of the average "dumb" alternator, which does not produce it's rated output continuously, and it does not need an ECU to adjust the output upwards as the load on the system increases (or vice versa) - how it works is as the electrical load increases the required current is drawn from the battery causing the battery voltage to drop, the alternator sees that voltage drop and increases it's output to compensate - if the load drops, the excess current goes to the battery causing the voltage to increase, which the alternator again sees and reduces it's output to bring the system back into balance - this is all done by the alternator's internal voltage regulator.

What the smart alternator does is allow the ECU to reduce it's output when the engine load increases and return it to normal when it decreases - this essentially "optimizes" the system efficiency by diverting the power from charging the battery to moving the vehicle, as an example, the alternator will be running at "normal" output (whatever is required to supply vehicle loads, and charge the battery) whilst you're sitting at a stop light with the engine idling, and as soon as you get on the gas to move off, it will cut the alternator output - as you accelerate to a "cruise" speed and the load on the engine is reduced, the ECU will ramp the alternator output back up.

At all times during this process, system voltage is tracked and if it drops indicating that the battery is becoming discharged - the ECU will reduce the frequency and amount by which it reduces the alternator output by to prevent the battery from becoming fully discharged.

The above can be verified by simply placing an ampere meter in the alternator output lead - with a "dumb" alternator what you will see is the output current spike immediately on start up and drop quite rapidly within the first few minutes of vehicle operation (this is the battery being recharged to "replenish" the energy used to crank the engine) - once the battery is recharged, the alternator output will stabilize at whatever value is required to sustain vehicle operation and you will be able to vary this by turning on/off any accessory of your choice - lights, blowers, etc. - try it - you'll find the alternator output will typically be less than half of it's rated output unless you have something switched on.

[ZUZUKI]

This could be a long & involved topic.
If you go back far enough....

Generator with external reg = dumb gen.

When they first came out, Alt with external reg = dumb alt.

Alt with internal reg = smart alt. - as in "A 'smart alternator system' - but plenty of people would not have termed it as such. 'Smart alternators' were much frowned upon by mechanics & auto elecs. in the mid-late 1960s when widely introduced. 'What was wrong with the old external reg. (dumb alt.) system? These (smart) alts. with inbuilt regs. do the same thing, but now the reg. is exposed to muck at the front of the engine, not tucked away on the firewall in a protective box & it's much harder to 'tweak' them up like we used to, now it's a throw away part'.
Quickly, these 'smart' alternators became the norm, so when further refinement of alternator operation was introduced (via ecus in the early/mid 2000s) these were 'smart' alternators all over again - really, smarter, smart alternators, with the actual alternator reverting back to a dumb alternator, just being told when to produce power by the ecu.

Alt with external reg (the ecu acting as an external reg) = dumb alt. but still a 'smart alt. system'
I agree current 'smart alt. systems' are even 'smarter' than they used to be, with more parameters to influence & be influenced by.
Some systems work in reverse to what you have mentioned, especially those that switch the engine off at the stop light = no alt. charge opportunity at idle, as there is very little time spent at idle.
These often do their best charging at 40+% throttle open position (varies) where the system says effectively 'must be after performance, not fuel economy - can afford to run higher alt. output & not have it be noticeable too much to the driver'.
If the throttle open position goes past 70+% (varies), it then goes, bugger, looks like driver is really after performance at all costs, reduce alt. output to reduce drive belt drag to retain as much of engine output as possible to move the car ASAP.
So...the next developments we will see in mainstream vehicles (smartarse, smarter, smart alternator systems?) will be combined alt / starter motors built around the flywheel & bellhousing - not using a belt drive, not using ring-gear teeth & starter pinions, but induction, operating at 36/48/72V - pick a number, but it will be higher than the previously universal nominal 12V system.
Some 'range extending' (via piston engine) but purely electrically driven cars have alternators like this, where the engine just powers an alternator to charge the battery pack, with no 'mechanical' link (like driveshafts) to the driven wheels.
The alternator, as we currently know it, is doomed.

But we digress (& get pedantic, sorry), whatever we call it, it won't be the cause of slow then fast wiper activity.
Rgs, Michael

[ZUZUKI]

Hmm, re-reading that, I can see it sort of looks like I've skipped a step in the alt. evolution.
Smart alts. of the early /mid 2000's onwards still had inbuilt regs. but with the ecu looking over the alts. shoulder, making sure other parameters the alt. didn't know or care about were being catered for.
The complete control of alt. function by the ecu is a more recent development.
Rgs, Michael