cadman_ks

We live in Kansas. If you've never been there, it's FLAT.

Took the GLE43 to Branson over the weekend, and they have some hills there. I didn't think too much about "needing" the hill assist, but it does work, but there's a caveat that just about caused us to slide backwards into someone.

It only works when you've come to a complete stop using the brakes.

Let me explain...

We were going up a hill SLOWLY in traffic, a hill that was big enough that at normal idle speed (I didn't have any accelerator applied) the truck would come to a complete stop, and hold itself there AS LONG AS THE ENGINE IS ON. That's where things got a little bit wonky. If the vehicle STOPS on the way up, AND it goes into ECO mode, IT WILL ROLL BACKWARDS! I actually had occasion to test this twice, and the results were the same both times.

It is a little bit unnerving when it happens. I suppose that the simple solution is to take ECO mode off, but I would have never thought of that in this situation. I was COUNTING on hill assist to work.

Another oddity about hill assist is that it only holds the hill for a VERY BRIEF period of time, so you have to be off of the brake and onto the accelerator QUICKLY, or it will start to roll backward. It actually states this in the owner's manual, and that's OK, but you still need to "know" that it works that way.

Have others noticed this same phenomena???

Tbone8771

Sometimes when I am on a hill, once I am stopped, I just press the brake pedal down harder and put it on brake hold until I press the gas pedal to release it.

cadman_ks

That's a good idea, and I've used it that kind of a way too.

But I did NOT expect it to allow me to roll down hill when the engine shut off in ECO. I don't even know if that's a hill assist issue or if that's something else. In my scenario, I didn't have any brakes applied at all. I didn't need them...

GLE43_Sube

Just to clarify, the "Hold" feature and "Hill Start Assist" are two completely different features that work independently. Hill Start Assist works automatically. You don't need to engage it. It momentarily applies the brakes for the instant between releasing your foot off the gas pedal and applying the brakes. This is designed to be easier on the transmission by preventing the car from rolling backward while the car is in "Drive". The "Hold" feature must be manually activated. It's designed for those times you might be stopped in a traffic jam or for a traffic light, and you don't want to keep depressing the pedal. I've also used it at restaurant drive-thru windows. Works great when you don't want to put it in "Park".

"Hold" will display on the screen when activated. "Hill Start Assist" doesn't display.

cadman_ks

Yes, you're correct on all counts, and I probably should have NOT titled this "hill assist", because that is confusing.

At the end of the day, the part that everyone needs to understand is that IF you're going UPHILL, and you slow to a stop WITHOUT touching the brakes, AND ECO engages, you WILL roll backwards.

Part of the reason that I titled it "hill assist" was that I was thinking that hill assist would kick in in this situation, but it does NOT...

GLE43_Sube

That's very useful to know. I never realized that. Maybe it's because I never use ECO. If I drove in LA freeway traffic during rush hour, where the car sits for more than it moves, I would probably use it. But for my situation, it's much more of a hassle. The A/C starts blowing warm air and I hate the abruptness of the engine re-starting. Even though I know it's there, it's still startling. I wish it was turned off by default.

cadman_ks

The A/C blowing warm air is the biggest nuisance of it.

One thing that I have been really impressed with though, is how quickly it does start back up. As a "user", it feels pretty seamless to me...

GLE43_Sube

It is seamless, but it still scares the hell out of me.

cadman_ks

LOL!!!

BACnMercedes

"Seamless"? I would use the term, aburpt. But I didn't think the eco would kick in and turn the car off unless your foot was pressing the brake enough for it to sense it. Mine will not cut off unless my foot is on the brake.

cadman_ks

That's exactly the reason that I wrote this post! I did NOT press the brake at all, and it went I to ECO mode. The first time it scared me, and I wasn't totally for sure if I had tapped the brake or not, because I was in somewhat of a panic mode as we rolled backwards. The second time I was totally aware of what was going on, attempting to repeat the situation, and I did NOT push the brake.

It was incredibly concerning when it happened...