Avoid it if you can. Batteries are double the price at least and changing them is not always straightforward. The technology exists for the benefit of manufacturers getting through emissions testing, rather than for any driver benefits.

Many cars with S/S have a button to disable it - some Euro 5 cars stay disabled or can be disabled using diagnostic software but Euro 6 cars need the button pressed every time - they have to use it as their certification was done using it.

Not a surprise ethat a Japanese car has an automatic disable feature the stop-start systems on turbocharged cars - to me, that's the sort of 'logical thinking' on the engineering side they are renowned for. I wonder if their European counterparts have thought of this. In a way, having it surely (partially at least) negates the usefullness of the stop-start system, given most 'stops' at traffic lights are well under a minute.

I think rather than using 'gimicky' technology like this, cars of the future (before full battery-electric etc come into their own and are affordable/fully usable over long trips) will be more like the supercars that have an IC engine to recharge the batteries, which in turn power the car's electric motors to give motive power, and will automatically kick in and out when the battery power reserve level gets low, whatever the car/driver is doing. it will, though, probably take away some of the 'thrill' of motoring without the 'roar' of the engine when you pull away at speed etc, unless they include the 'fake' engine sounds!

My tuppennyworth;

I had reservations on the s/s when purchasing my Mazda 6 petrol sport last year, but the fact you have a switch to deactivate or if you keep the clutch depressed, I went ahead.

I have become converted, rather than switch it off you can keep the clutch depressed to cancel, and most of my driving style is so.

The techy bit is something I like, (yes more to fail and cost but heyho and capacitors generally are pretty basic and robust components) it uses a large capacitor to store electric generated when decelerating or braking, then uses this to fire up the starter motor. Together with 'managing' to stop the pistons in a way to re-use the very high compression stored in any piston. Apparently the 2.0 ltr petrol is the highest compression engine used by any mass manufacturer. Whoopy do, I know some peeps worry about H Gasket failure!

IIRC compression is 12:1 where F1 race cars are/were 10:1 and diesels (which I thought were higher than traditional petrol equivalents) are 8:1. But I may be wrong, there are always exceptions.

The capacitor power is also used to run all the electrics including air con, and to extend the few minutes you have when stopped I switch off air con say when in a traffic jam for long periods. I have found it works very well and you get a readout of cumulative minutes 'stopped' and IIRC a saving measurement of fuel?? I think you can reset this measurement but I think mine has been reading from new.

Sorry for long message, just trying to be helpful, anyone finding fault can .... well just cool it.

I do know that it can be coded out on BMWs. But actually being able to do it is a bit geeky high-tech for me.

So I'd imagine yes, it could be done. But you'd need an owner's forum, and then someone highly capable or yourself to be highly capable to do it.

There is always the risk of 'bricking' your software too - which means what it says - basically something isn't correct, and it all becomes as useful as a brick.

I'd like to permanently disable my slk stop start, I can't abide it. Any one know how to do it?

If it's Euro 6 it shouldn't be possible, even with full dealer diagnostic kit, as it's been Type-Approved with it working - it's technically illegal, like disabling the EGR or removing the cat (or DPF on a diesel) - but I'm not sure how it could be detected.

My Verso 1.6 D4-D is Euro 6 and has a press button on dash to disable Stop-start - but most of the time I now leave it switched on.