Front park sensors sometimes late/nonfunctional?

This is on a 2016 HSE. I noticed sometimes with the park button illuminated, meaning the fronts are active, sometimes I creep up to an object in front of me to see if they come on, and they don't (no beeping nor screen display of the graphic). Sometimes they do but they're delayed, uncomfortably delayed (can hit something in that case).

Any ideas what's going on?

I'm of no help other than offering my own experiences.

Our 2015 LUX experiences random parking sensor warnings while backing up, assume its a sensitivity issue. The blind spot indicator flashes randomly as well on highways with no cars around.

I find the warnings highly distracting even when operating properly.

The only warnings I find that work great are the cross traffic. That portion of the technology is great in my book.a

Unfortunately that front parking sensor behavior is normal. Sometimes it senses an object and other times it has no clue. I have even noticed this pulling into my garage. Sometimes it sees the wall, other times nothing. At least the rear sensors seem to pay better attention, probably because selecting reverse activates them.

I end up pushing the front sensor button off and on when pulling in the garage anymore. That seems to trigger them and the front screen.

That's normal. The fronts turn off after you drive away from parking and exceed a preset speed, and stay disabled until you either enable them manually with the button or engage reverse gear first.

umbertob said:

That's normal. The fronts turn off after you drive away from parking and exceed a preset speed, and stay disabled until you either enable them manually with the button or engage reverse gear first.

Click to expand...

But the P button is illuminated during the times when I expect it to beep (and show the display too), i.e. the car is doing <10mph.

So it seems I'm echoing PaulLR3's findings.

If the P button is lit, there's no reason for the front sensors not to detect and beep for anything in front of the car close enough. But it seems to not do it, sometimes.

Coming from a '14 Jeep Grand Cherokee Summit with front park sensors, it's odd to me the front sensors have to be manually enabled when pulling in. On the Jeep they activated automatically when the vehicle was in Drive and got below a certain speed limit - worked really well. Oh well, just have to get used to hitting a button.

rdrakea said:

Coming from a '14 Jeep Grand Cherokee Summit with front park sensors, it's odd to me the front sensors have to be manually enabled when pulling in. On the Jeep they activated automatically when the vehicle was in Drive and got below a certain speed limit - worked really well. Oh well, just have to get used to hitting a button.

Click to expand...

It is not intended that way, and it does often work for me to automatically sense objects (without pressing a button) so it isn't that you have to manually turn them on, just that they might not be as sensitive or intelligent as would be expected

I think we should all go take another good look at the Owner Manual's Parking Aid section before sentencing that something must be wrong with these sensors, as there seems to be a bit of confusion about their correct operation. Just because those in a Mercedes, Jeep or Kia may work differently or be more sensitive, doesn't automatically mean ours must be broken.

Among other things, our manual states that the sensitivity of the front sensors is way, way lower than the rear ones, only about 24" (vs. 60" for the rear center ones when you're backing up.) They are ultrasound sensors, so they aren't infallible and can miss or be tricked by thin posts, non-reflective dark surfaces, parked stealth fighters, dog trainer whistles, etc. They will turn off - and stay off - once your vehicle exceeds 10 mph, until and unless you engage reverse again (or push the button to turn them on manually.) So, if you pull into a garage after a drive that exceeded that speed, you'll crash into that pole in front of you if you are waiting for the sensors to warn you.

My front ones work as expected, meaning they are often off when I need them most - but that's fine. Frankly, they are pretty useless to me even when the are on and beeping like crazy, I can see just fine and judge distances pretty accurately in front of the hood. I'm just a natural at that kind of stuff, must be all the practice I got behind the wheel in the 80s and 90s, before these gizmos for Millennials were invemted to save us from ourselves. That's one bit of semi-useless technology - like swiveling headlamps, rain sensing wipers and digital oil dipsticks - that I wouldn't miss for a second if someone took it away tomorrow. The rear sensors (and camera) are much more useful and actually work automatically when you expect them to - when you are backing up.

umbertob said:

I can see just fine and judge distances pretty accurately in front of the hood. I'm just a natural at that kind of stuff, must be all the practice I got behind the wheel in the 80s and 90s, before these gizmos for Millennials were invemted to save us from ourselves. That's one bit of semi-useless technology - like swiveling headlamps, rain sensing wipers and digital oil dipsticks - that I wouldn't miss for a second if someone took it away tomorrow.

Click to expand...

^^^Completely agree, I think the LR4 is one of the easiest vehicle to judge distances up front. The front corners of the hood are pretty close to the front bumpers of the vehicle. As for all the new technology, I prefer to drive myself and have never even used speed cruise control. I am sad to see that manual transmissions are nearly extinct. I'm thinking about replacing one of our LR4's with the new Q7 because I like the way it drives and handles. I really don't care that it can brake itself, stay inside marked lanes, or drive itself in stop & go traffic.