It’s not the spec of the battery that matters, it’s the aging factors. As they get older they need more energy to charge and the discharge curve changes. So all your electronics (and alternator/generator outputs may need to be tweaked).
So the car just needs to be told that it's been replaced? There are various part numbers and coding for those parts in VW, not sure how much it matters.
Depends how shagged the battery was when you took it out.
Not really shagged. It still started perfectly well, just the start-stop didn't work much.
So the car just needs to be told that it’s been replaced?
I bought a used Fiesta for my daughters and it came with a new battery - but the stop/start didn't work. A bit of googling showed that there was a short series of actions* that told the car the battery had been replaced. Worked as expected after that.
*
Ign on for 10 secs
Press fog lamp switch 5 times
Press hazard switch 3 times
Wait up to 10 secs while watching battery light
Battery light flashes
Ign off.
So the car just needs to be told that it’s been replaced?
Essentially, yes. The car knows the spec of the battery, and the curves etc when it's a new battery. Then adjusts as the battery degrades.
There are various part numbers and coding for those parts in VW, not sure how much it matters.
How many wires did you connect to the battery, more than two. i.e. Does the battery have it's own ECU?
If not, coding and part numbers means nothing.
Quick work of warning on this subject. My 80 Y/O dad had Halfords replace the battery on his stop/start Ford Kuga and it never did seem right and hardly ever start/stopped anymore. less than 2 years later he’s had a load of random electrical problems that have been traced to a duff battery.
The battery had a five year warranty but Halfords flatly refused to look at it as apparently “you have to remove them every once in a while to charge properly”. Which is clearly horseshit as the car sees weakly use. I have escalated it on his behalf but hit a brick wall from their customer ‘service’ as a result of this Halfords have made sure they’ll be getting no more of my money as I think it’s pretty poor form.
How many wires did you connect to the battery, more than two. i.e. Does the battery have it’s own ECU?
I think there's a few all bundled into the same connector. I'll have to do some more reading.
@reeksy I take it its a Giorgio platform car of some sort. They are so notorious for it. Practically the only thing that ever goes wrong with them. My Giulia ate its factory battery at 18 months. I half-joke that the mafia knicked half the lead from the factory during production.
The IBS that monitors the battery health under the boot floor may need a software update, but 90% of the time its the batt itself that has gone. Other symptoms will be the heated rear window will refuse to demist.
The only thing you can do is replace it. Then you need to bung it on charge overnight connecting via the IBS negative terminal in the boot (the post that the arrow below goes over, not points at).
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Thanks @hot_fiat - it's a diesel Stelvio. Never have a need to use the demist in Queensland (or and of the heated seats, wheel etc), but i'll check it all out.
The only thing you can do is replace it.
You mean the battery?
Why do i need to do an overnight charge on a new battery?
I have a 2013 1.6 diesel Doblo with stop start. I got the car at 2 years old. Stop start never worked reliably, and when it did kick in I would shi*e myself thatthe car had broken down.
The battery looked fine on every test I could reasonably do, but replacing it solved the problem entirely and now it works all the time.
Yes replace the battery not the IBS.
The overnight charge through the IBS tells the unit that it’s a freshly charged battery.
Alternatively I think you can do it via the EOBD with MES by setting a flag in the ecu but you’ll need a license. At 5yr old I doubt you’ve a security gateway so it should be pretty straight forward.
You know how to clear the post battery change array of warnings? In a big car park, park up, switch car on, into Drive, go forward a little and go full lock to the left, then full lock to the right, left and right again. Should shut it up.
Also: the quick negative connector that is actually highlighted in the picture - after you’ve changed the battery make sure this is well and truly seated and clicks home. Give it a proper wiggle. I’ve seen a few garages fail to reconnect them with panicky posts from people saying “ooh my Alfa died with loads of errors”, when in reality the poor thing suddenly didn’t have a battery for a few seconds as they drove over a bump.
And all that^ has just reinforced my prejucide that this is a botched solution looking for a problem. No thanks. 🙃
And all that^ has just reinforced my prejucide that this is a botched solution looking for a problem.
What is a botched solution? The battery management stuff is nothing to do with start/stop.
Start/stop works, it saves fuel and reduces pollution. Don't worry about it any more than any of the rest of the million things in your car that can fail.
When you're cycling in town would you rather ride down the side of a queue of cars producing pollutants, or a queue of cars not producing pollutants? If you live near a junction, do you want cars sat outside your house all day idling, or off?
I really like start-stop in the Giulia. It's very seamless and there's loads more going on under the hood with electric circulating pumps for the water, the chargecoolers and most importantly the oil which keeps all the pressures at idle levels or higher and prevents boiling in the turbo bearings on the exhaust side.
Whereas on our old kodaiq or the T6 it seems like a bodge. It triggers too soon (you've often not stopped) and then springs back into life as it realises its mistake. There's an electric water pump, but that only kicks in if you've been giving it the beans, so really you're getting proper engine startup wear all the time.
Blimey, all this complicated shenanigans for a battery. Mixing Alfa's and electronics is always a bad idea. And yes, I had one, a 147 Selespeed when they came out, and it was forever going back to the dealers with electrical issues. Lovely car mind. Had to Microsoft 'reboot' it regular. All the components were Bosch but what ever the Italians did they messed it up.
Some mild hybrids do cut out early, if you are going slowly and lift off - but this is by design. Our hired Kia did this (when it felt up to the task, which was rarely)
There’s an electric water pump, but that only kicks in if you’ve been giving it the beans, so really you’re getting proper engine startup wear all the time.
Why does having an electric water pump make the engine wear?
I'm struggling with electric pump = engine wear.
I changed cars recently. It was not activating the stop/start at point of purchase. To be honest, I hadn't even clocked that it was a feature on the car. Two days later it was doing it every stop consistently. Seems like battery management simply wanted to see more charge in the battery to meet the criteria for enabling the feature.
VW only fit a coolant pump as a sort of half-arsed concession to the fact the engine is randomly off. When it does, the oil pressure drops to 0 and all the journals will start to drain. You'll subsequently get warm start-up wear when it fires up again. That doesn't happen on the alfa as the oil pressure is maintained, piston skirts and bores continue to get sprayed, turbos get fresh oil circulated through them as well as their bodies cooled.
Well weirdly enough this morning the low oil light came on. I topped it up on my way home from work… and now the stop/start is functioning properly for the first time in weeks.
Surely a coincidence, but nice nonetheless.
When it does, the oil pressure drops to 0 and all the journals will start to drain.
Not exactly true - although the oil is not pressurised it's restricted from returning to the sump so there's oil there when the engine restarts.
Whereas on our old kodaiq or the T6 it seems like a bodge. It triggers too soon (you’ve often not stopped)
Stop in drive at Speed, extra emissions savings, it's meant to do that, usually 3kph in a conventional ICE (non-48V) ndue to system safety requirements (related to brake vacuum and steering loads IIRC)
and then springs back into life as it realises its mistake.
You're reducing pressure on the brake pedal (loads of people do it), or the brake pressure calibration isn't very good, that triggers a restart.
There’s an electric water pump, but that only kicks in if you’ve been giving it the beans, so really you’re getting proper engine startup wear all the time.
???
Coolant circulation has no impact on engine startup wear, not with a warm engine. Oil circulation *might* but only if you're standing for several minutes. Most stop start engines i've seen have non-return valves or restrictors in oil galleries to prevent this, or slow it down massively.
@mert You sound like you're intimately involved in this area. Is that right?
Yes, i've been doing this for 20+ years.
K. So, I admit to a lot of (maybe blind) prejudice but I work on the principle of the simpler the better with vehicles.
They've got to a point where repair costs of insanely complex (often non essential) elements are making repairs non cost effective and so writing vehicles off. Very wasteful.
I've also worked on the principle that the less you stress a machine, the longer it lasts. So stopping and starting something 1000's of times more than strictly necessary *must* have consequences beyond the fuel/pollution savings.
Typically what's the fuel saving payback on a 2l diesel vehicle average use profile/average mileage please?
VW only fit a coolant pump as a sort of half-arsed concession to the fact the engine is randomly off.
I think the electric water pump is to circulate hot coolant through the heater matrix to keep the warm air blowing when it's stopped. There could also be an electric AC compressor for the same reason.
They’ve got to a point where repair costs of insanely complex (often non essential) elements are making repairs non cost effective and so writing vehicles off. Very wasteful.
It's not quite like that, I don't think. MOST stuff is the same as it always has been, but there is certainly more of it. Most of it is to do with reducing pollution - so what would you rather?
And really - cars are better than they have ever been. The reason that working cars keep getting scrapped is because people at the other end of the market keep buying new ones. That means there's simply too much supply. People don't want to spend more on a repair than the market value (which I think is absolutely the wrong way to look at it) and this calculation can be affected by the high cost of repairs OR the low cost of a replacement.
Typically what’s the fuel saving payback on a 2l diesel vehicle average use profile/average mileage please?
It's not just about fuel cost, it's about pollution.
So, I admit to a lot of (maybe blind) prejudice but I work on the principle of the simpler the better with vehicles.
It's never simple. A simple petrol engine is going to be noisy, inefficient and/or underpowered, and pollute a lot.
I work on the principle of the simpler the better with vehicles.
Jeepers, you missed that boat decades ago!
I’ve also worked on the principle that the less you stress a machine, the longer it lasts.
I would imagine that simply driving a car is more stressful to a car than a warm start.
Typically what’s the fuel saving payback on a 2l diesel vehicle average use profile/average mileage please?
That will depend on where you drive/how many times you stop!
On an WLTP emissions cycle with active stop start system will save you about ~1.5% fuel economy.
No idea what a "normal user profile" looks like. So i couldn't tell you.
But in heavy traffic city driving, with lots of stop start and such like you might get up to 10% on a short, cross city, journey compared to not having it.
On my drive to work it saves me about 0,0001% of nothing because i have a long drive and virtually no lights or traffic to contend with.
I’ve also worked on the principle that the less you stress a machine, the longer it lasts. So stopping and starting something 1000’s of times more than strictly necessary *must* have consequences beyond the fuel/pollution savings.
Stress usually isn't something you worry about until something is being asked to work outside it's design criteria.
And this duty is designed in. (And typically, in a 12v ICE it'll be around 10-12 times the number of starts, not 1000's. Maybe triple that in a 48v car. Also, starting the engine from a vehicle instructed stop typically takes around 1/10th the load of a key start. There are even some that can start using ignition/fuel injection rather than the starter. I've played with it, and we have built some protos, but it never went to volume as 48V ICE took off, and that doesn't need it. In fact, we reviewed removing the engine speed indication/rev counter for 48v cars, but the engine start (soft start) is so inobtrusive that it's sometimes not possible to tell if it's running or not.)
They also have upgraded of modified ring gears, starters, batteries, fuel pumps, injectors, restrictors or non return valves in oil channels etc etc.
FWIW the total hardware upgrade cost to add stop start to a 12V ICE car in the first place was so low that other than the battery + extra harness ($$) and starter ($), most of the changes we made to the rest of the car we just included in all cars because it was easier than having multiple part numbers
They’ve got to a point where repair costs of insanely complex (often non essential) elements are making repairs non cost effective and so writing vehicles off. Very wasteful.
Much of that is legally mandated emissions equipment, if you're talking powertain/stop/start/engine. If you'd all been driving round with stop start active for the last 15 years, we might not have needed all of it. (i joke, of course we would...)
Would be interesting to hear what you think it "non-essential" though. From a that powertrain perspective.
If you want to try scary stop start, try the latest 48v cars with coast and sail functions.
Lift off the pedal at up to 180kph and the engine disengages itself from the road wheels and then switches itself off until you hit one of half a dozen exit criteria. One of which is stopping... Think the next gen audi's are going 200+
Very wasteful.
Everything about consumer goods is wasteful in one way or another.
Everyone's trying to do something about it (as it's profitable to be less wasteful) but the first one to blink and actually do something concrete about it will probably be the first to go bankrupt.
There are a few initiatives around recycling and reuse, but nothing (yet) properly joined up, except for (sort of) recycling and reuse of EV batteries. Which will take a while yet.
Lift off the pedal at up to 180kph and the engine disengages itself from the road wheels and then switches itself off until you hit one of half a dozen exit criteria.
That's all very interesting info @mert - love it!
I know some cars drop their rpm to idle levels when coasting - how does that work?
it’s about pollution
Time to burn the Witch - I don't care about this. Or rather, it's not the primary driver. The amount of driving I do now, any efficiencies would be offset by some **** with a 2s lawnmower on his/her/its Sunday cut.
Jeepers, you missed that boat decades ago
Yeah I know. Compulsory 'upgrading' hence all the bellyaching. We have no choice (other than to buy a Series 1 I suppose) but to accept all the bells, whistles, knobs and knockers (not stop/start specifically) which add weight, complexity, cost and often, accelerated obsolescence. The cost of trundling all this shit around is real but we're mythering about my reluctance to embrace a 1.5% stop/start saving as the Holy Grail...
That will depend on where you drive/how many times you stop
Yeah I know, but when they (Mert) design stuff, they tend to make assumptions (guess) and take them into account as design/use parameters.
this duty is designed in. (And typically, in a 12v ICE it’ll be around 10-12 times the number of starts, not 1000’s
I meant over the life of the assembly so I'd image a 'normal user' (sorry, there must be a set of useage patterns stuff is designed against Shirley) will do 1000's of extra stop/starts even on Ye Olde 12v systems?
Would be interesting to hear what you think it “non-essential” though
I was thinking more generally about short life/built in obsolescence. Glass dashes for example. How many of the current crop will be scrapped in ~10 years because of a dry joint in their £5k TFT 2 foot long 'instrument cluster' when the cars residual is less? They do it because 'the customer wants it' when actually, it's probably just cheaper to make...
Everything about consumer goods is wasteful
Yeah I know but I choose to repair (within reason) rather than throw away. I buy white goods with 'guaranteed' for 20 years parts availability (whatever that means: 'have a seal Mr Lo, that'll be £1m please...' ). I also try and keep stuff beyond the exciting 'new, new, new' phase and use 'till ferked rather than just spaffing consumerism. If stuff is sold in a way that's inherently difficult to live with longer term, it makes that very difficult. I'm not talking about keeping a car for 40 years but I am thinking it shouldn't be fit for the tip after 10 - like the shit produced in the 70's but for different reasons.
Sigh, I sound like my Grandad. Sorry.
The stop/start went seasonal on my VW when it was about 5 years old (original battery) and gradually got worse until it stopped working completely at about 8 years old.
But I’m a skinflint and didn’t replace the battery until the car failed to start altogether in the depths of winter a year after that.
Stop/start went back to normal with the new battery.
I know some cars drop their rpm to idle levels when coasting – how does that work?
Usually by disconnecting one of the clutches in the gearbox, which clutch depends on if the box has an electric or mechanical oil pump. Problem is that in some cases it saves more fuel to keep the box connected and send the engine to fuel cut (zero consumption) and let the car decelerate very slowly, in coasting, it still uses a little bit of fuel to keep the engine turning over.
tend to make assumptions (guess)
Yeah, it's a bit of WLTP, bit of NEDC, bit of Real Driving Emissions a load of statistical data from test/customer cars. But the definitive thing is always the emissions certification. Hence the 1.5%.
And i can vaguely recall a standard starter is rated for 65 or 75000 starts and the stop start version is something like 300-350000.
They do it because ‘the customer wants it’ when actually, it’s probably just cheaper to make…
TBH, it's both. The customer wants it (because marketing), and we need to do it as cheaply as possible to remain profitable, also, we have to keep up with our competitors, who are also doing it.
And i can vaguely recall a standard starter is rated for 65 or 75000 starts and the stop start version is something like 300-350000.
Interesting to know that. My in laws are convinced stop start will kill the starter motor.
accept all the bells, whistles, knobs and knockers (not stop/start specifically) which add weight, complexity, cost and often, accelerated obsolescence.
I think that a lot of the additional weight increase has come about in the name of safety.
