Battery and i-stop

[BigAl]

OK, I have an issue with my 2018 2.2D Sport Nav auto in that the i-stop isn't working. This happened about 4 months ago, it worked less and less then stopped altogether. So in went in for two days to have a full deep recharge (stood in water...) which cured it. That was about 10 weeks ago, it worked fine for a couple of weeks then declined and finally stopped working again.

I had the same thing happen on my previous CX5 (same spec but manual), in the end the battery was replaced by Mazda after a couple of deep recharges.

It's been "suggested" that the problem is down to me not braking hard enough for the i-eloop system to keep the battery topped up. According to the dealer, I'm not the only one noticing this issue. I didn't think the i-eloop was UK spec as there's no screen for it on this car (but was on the previous one).

If it were only the i-stop that was affected it wouldn't be bothered. However I have a dash cam that runs on both switched and permanent live feeds, via a Power Magic unit. That monitors battery voltage and shuts the dashcam off if the battery voltage drops to prevent draining it. So, currently it keeps turning off as well (which you don't always notice) and it then has to be reset which is a PITA.

Anyone else had this issue?

Alan

[aljshep]

In the past four years we have had two new Mazda 6s and two (almost) new CX-5s.  I switch from one to the other almost daily.  All have had i-stop and none has had a problem with it.
When available it can be controlled at rest by pressing down hard on the brake or otherwise.
The condition of the battery has no relevance apart from the fact that it is needed to run the electrical system whilst the engine is stopped.  The battery is not used to re-start the car.

Both “sixes” had i-eloop.  The capacitor (not the battery) is charged when the car is moving and if one's foot is off the throttle.  Braking has no relevance.  As far as I am aware, no CX-5s have/had i-eloop!  Cars with i-eloop have high capacity batteries compared with cars which do not.

So, I am completely surprised at what your dealer has told you – on two counts.  It does not make sense.  Could it not be that something in the car is not switched off properly and that is what is draining the battery.  Could it be the Power Magic unit?  I do accept that i-stop may not work when the battery is low as there might not be enough capacity to run the radio and lights etc.

[BigAl]

The i-stop's ability to function is actually dependant on the condition of three things - the engine, the battery and the AC. Those are the three items on screen, all have to have the "halo" around for i-stop to operate.

When last tested, the battery "condition" was poor. The deep recharge procedure was needed to bring it back into a good state. This is a known procedure for Mazda (although I'd not heard of it before), where the battery is removed from the vehicle and recharged with the battery standing in a water bath to control temperature. This can take over 24 hours to do.

I suspect you may be right on the drainage, though. It may be that the lower voltage threshold of the Power Magic is lower than that needed for the i-stop system to be activated. Maybe will disconnect the permanent live feed for a while.

Alan

[Anchorman]

Your car doesn’t have Iloop as suggested.  Try connection your power magic supplies via the accessory ports so they only charge when the engine is running. They may be talking a tad too much power before reaching their own cut out level.

[BigAl]

Your car doesn’t have Iloop as suggested. 

You know, that's what I thought. I didn't think it was UK spec which was why the screen is no longer on the system. Dealer is telling me it is. Will have to check this with Mazda UK.

[BigAl]

Update - problem solved.
Removing the dash cam Power Magic unit and reverting to the cigarette lighter socket for power resulted in the iStop working again within 24 hours. That was last week and it’s still all good. It does mean that I’ve lost the parking operation of the dash cam but everything is now as it should be.

Spoke with Mazda UK and they confirmed that iEloop is definitely NOT fitted to UK spec CX5’s. Have made the dealer aware of this.

Alan

[Anchorman]

Good work al.

[david1812]

I have bought a new Sept 1st 19 CX-5. within two and a half months the i-stop ceased to function. It went in to garage for warranty where I was informed that when (not should) the battery deteriorate to about 70% of charge the i-stop will cease to function. Summer months, therefore low electrical usage.

One supposes the garage recharged the battery prior to my collection seeing as it operated properly thereafter however ....

Within a week it ceased to function once again.

It has been returned to the garage. who say they are going to pursue the mater with Mazda. However it being a Euro6 engine, I assume emissions are part criteria to meet regulations and therefore if i-stop is not functioning emissions are being expelled all the time a vehicle remains stationary with engine running.   

Does this compromise their accreditation. No sales literature mentions this fundamental system failure and I am led to believe these vehicles are not Fit for Purpose under the Consumer Rights Act 2015.   

Now lets see if Anyone at Mazda reviews these forums and offers a explanation as to why I should not pursue this through the European Parliament and / or Courts !

[Anchorman]

I think you posted on 24/7?  There is a long list of conditions that need to be met before it will work so have a read and see what happens. You’ve probably got something with a high drain or heater extreme or seatbelt etc.

[david1812]

Nothing more than listed electrical items. maybe all that is running is A/C heating. if it can't handle that then it's insufficiently powered at source.

[MikeTB]

Doesn't make any sense to me. If there is a battery problem the first effect is usually problems starting.
My car is 6 years old and has a very low mileage. I-stop works as normal (i.e. when it feels like it).
I have checked the battery which is the original and it still holds its voltage fine.
Unlike my second car where a new battery has gone completely flat 3 times but dealer could not find any faults with it.

[david1812]

Your comment regrading i-stop tells all. You said it operates when it feels like it ! In other words pretty damned useless, unless it is operating at all times otherwise what's the point of having it ! 

[Anchorman]

The parameters are set and laid out in the handbook.  It’s either something you’ve set like AC or demist or there’s something wrong. The system works perfectly.

[AndrewT]

It took me about 6 months to realise that i-stop only works if you press the brake pedal down a certain distance, - light pressure which is normally enough to hold the car stationary (mine's auto) is not enough to trigger i-stop, as you say there are other factors which block i-stop, but it works well, and I really like being able to control it by brake pedal, unlike my wifes BMW that stops the engine given the slightest chance!
Andrew

[MikeTB]

Your comment regrading i-stop tells all. You said it operates when it feels like it ! In other words pretty damned useless, unless it is operating at all times otherwise what's the point of having it !

There are so many factors deciding when it should operate it just seems like when it feels like it. It doesn't work unless all the conditions are right.