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Start/stop update

I have posted here before about the stop/start feature on my Cherokee. For those who are not aware of what this is, it is a fuel saving feature wherein the engine automatically stops when you stop the vehicle, then restarts when you lift your foot off the brake or shift into neutral.

This feature has worked intermittently starting about a year after I bought the car (in Feb. 2015). I have had 2 software updates and had the battery sensor replaced twice. The last time was last Tuesday. Now the dealer is telling me that the reason for this malfunction is the fact that I do not drive the car often enough. After they replaced the battery sensor this last time I was advised that in order to get the function working again I had to drive it 3-5 times for 50-60 miles without turning the engine off, then when I park it, to not turn the engine on again for at least 4 hours.

Any thoughts?

Underdesigned…can you have this gimmick disabled?

I’m guessing the computer that decides whether to activate that feature or not has to first make sure the battery has enough juice to restart the engine. It does no good to Jeep sales to tout vehicles that turn the engine off at stop signs, then find out the battery is discharged & not capable of starting it up again. It takes quite a bit of battery charge each time the engine is cranked. The more frequently you drive, and the more in freeway type driving, the more charge the battery will have stored up, so it follows that type of driving is required to be able to activate the start/stop feature. I agree with @insightful above, also, it seems like the system isn’t really designed robustly enough. Plus having to replace the battery sensor twice already doesn’t breed confidence that Jeep engineers have selected the right technology for this application. I’m a frequent pedestrian and notice during walk-a-bouts there’s lots of makes and models of cars these days that stop and start their engines at stop signs, so such a thing can be designed robustly. It may take Jeep another iteration or two to get it right is all

I don’t think that is a question of being robust enough, the start/stop feature just isn’t useful for short trip driving. The engine temperature, catalytic converters and battery must meet a certain threshold before the start/stop feature will be enabled.

Driving 60 miles frequently to recharge the battery won’t save any fuel, you might consider using a battery charger instead.

I would just forget about that feature, it can only improve the fuel economy 1 to 2 MPGs when driven long enough to be active. If you stop complaining about it the dealer won’t be replacing random parts in an effort to satisfy you.

I personally would not buy that option but pull the fuse, or disable the software. How many major traffic jams do you have in Rapid City, if that’s where you are?

My sister leased a 2016 renegade, they told her to come in every 6 months for a computer update, maybe that is all you need.

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Insightful: In that it’s not currently working I would say it’s already disabled.

George: I agree.

Nevada: If my currently cycle doesn’t get it going I will give the dealer one more shot (they indicated they would keep it for 2 or 3 days to check it out thoroughly).

Bing: Actually, I live in Sacramento, CA. We do have a few, although I don’t to a lot of freeway driving and when I do I try to avoid commute times.

Barky: Just had a computer update a few weeks ago, but the way technology advances it may well need yet another one.

Based on all the feedback I’ve read and heard so far, I suspect this start-stop feature won’t last. There’ll continue to be new “computer tricks” to squeeze an extra millionth of an mpg, but consumers don’t seem to have been appreciative of this particular magic trick.

I know I wouldn’t want it.

Dreadful idea works dreadfully. Kill it.

Start/stop has been ubiquitous for at least a decade. I had it on a BMW diesel rental in Austria around 2012, and it worked flawlessly. I thought it was weird at first, but I eventually got used to it.

my coworker had it on her BMW 428 here in Virginia and she was irritated by it to some extent, asked mechanic if it is possible to disable and said it was a programmable option. I’m not sureif she eventually disabled it or not as she left the company shortly after

The thing is when you get a few hundred thousand miles on your car and its ten below out, the last thing you want is for the car to shut off at a stop light. It may not start again.

It is unlikely the start/stop feature would activate in that weather but if it makes you nervous push the button to switch it off.

It has existed in mass produced cars for a decade, but I wouldn’t go so far as to say it’s ubiquitous. The overwhelming majority of cars sold these past ten years don’t have it. Only a few manufacturers agree using it, and only on a few models. I only gained a first-hand experience with it a few months ago. I though it was weird to the max.

I’d think it would have the least “return” on a diesel, which takes less fuel to idle and more juice to start than a gasoline engine.

Update: it turns out the battery itself was dying (when I took it in in April I had them check the battery and the charging system and they said both were OK). They replace the battery (under warranty) and it seems to be working fine for now.

So, start/stop is working again? Can you disable it?

Insightful, there’s a button on the dash to turn it off. However, since the majority of my driving involves urban driving with a lot of stoplights, I would rather use this feature.

Have you driven a month with the feature off and then a month with it on and checking your MPG the proper way ?

Glad you got your stop/start feature fixed there OP. Good for you. With a new battery you’re good to go for the winter.