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2017 Jeep Grand Cherokee - HSA no longer holds

Recent problem with Hill Start Assist (HSA). When parked on an incline (driveway), start the engine and put it into Reverse, the Jeep rolls backward, causing a noticeable jerk in the transmission when Reverse is engaged. For automatics, HSA is designed to mitigate roll back from a complete stop while on an incline (per owner’s manual). HSA holds the brakes for about two seconds while you put the vehicle into Reverse. This prevents putting it into Reverse while the vehicle is moving backwards. My HSA no longer brakes for about two seconds, causing the noticeable jerk when Reverse is selected.

Take a look at the manual , it (HSA) may have been accidently shutoff and you may have to reactivate it according to the manual . Your manual will have the info on how to turn it on or off . Follow the instructions . Also didnt know you could even shift the car without having your foot on the brake . You should keep your foot on the brake when you shift anyway .If you can shift the car without having your foot on the brake you have an issue with the shift interlock that should be looked at .

Have you considered using the brakes to keep the vehicle from rolling backwards? This vehicle has an automatic transmission. It’s not like you’re having to modulate the clutch and gas pedal to get moving from an incline. But anyway check the vehicle settings menu to see if it’s been disabled.

I do have my foot on the brake. If did not, could not shift to Reverse. Car rolls backwards while I have my foot on the brake and before I shift to Reverse. I will try to see if HSA is engaged for sure. UConnect shows that it is enabled.

Have you tried using the parking brake? Still under warranty? Maybe it might be just a simple adjustment.

You need to get that car into the dealer for repair under warranty. NO car should roll backwards, with or without HSA, with your foot on the brake.

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As another person said , if you have your foot on the brake to shift it then it should not roll back HSA or not . Head to the dealer ASAP if this is actually happening .

I agree but it’s actually worse than that:

Before you shift to reverse, it is in Park. So it’s sitting there in the driveway on an incline, start the engine, step on the brake and it rolls backwards? Something must be wrong in the problem description…

See if the dealer can fix your foot.

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my dealership has the same attitude as yours

Not sure what you mean by this post . But I don’t think you have answered the question about your vehicle rolling backwards with your foot on the brake . That should not happen .

Have you demonstrated this to the dealer? What do they say?

Is it still under warranty? I’d think this is covered under the longer power train warranty.

yes it is under warranty and yes I demonstrated it to the service dept manager on an incline on their property. I was told he would research the problem and talk to Jeep if he had to and call me back.
That was 18 days ago.

You can get warranty repairs from any Jeep dealer. Don’t sit on your hands for 18 days. Be proactive, look in the back of your owners manual and go over your dealers head. The next step is probably the zone rep. Document everything. If it is phone calls note the time and day and persons name. Send them an email summarizing your understanding of the conversation.

Hill Start Assist;

“The HSA system is designed to assist the driver when
starting a vehicle from a stop on a hill. HSA will maintain
the level of brake pressure the driver applied for a short
period of time after the driver takes their foot off of the
brake pedal. If the driver does not apply the throttle
during this short period of time, the system will release
brake pressure and the vehicle will roll down the hill.”

If your vehicle moves while applying the brake or when using the HSA you are not applying sufficient brake pressure to hold the vehicle at a stop.

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If you haven’t elevated your complaint to the corporate level, you need to do so immediately.
Contact info can be found in your Owner’s Manual.