Hill start noise

[tucktuck8]

Alright so i've posted about this before but had a tough time explaining the noise. When I'm on a steep incline and let off the gas I roll back, as I'm rolling back I press the accelerator and it makes this noise until I am moving forward. Also, At no point does the "hill start assist" stop my car from rolling backwards. It doesn't sound like a normal noise a car should make. Imagine if you were to flick one of those door stop springs. sounds like that. Anyway I have a video of it happening.

It made this same noise when I was butted up against a curb going forward and I hit the gas to crawl over it.


Turn volume up
<iframe width="420" height="315" src="//www.youtube.com/embed/ABfEcyX8klI" frameborder="0" allowfullscreen></iframe>

first time posting a video let me know if it shows up.

 

[Cornelius]

Yup, that would definitely be your "Hill Start Assist" in action. See how well it works? :der:

I had the same question a while ago and thought something must be wrong with mine, and after reading a bunch on these wonderful ol' forums, I came to the conclusion that all the Hill Start feature does is make a bunch of noise and scare the s**t out of you. That's all.

I'm sure others will chime in pretty soon here. But in my opinion, you're totally fine.

 

[kevinpt]

all is good. mine does the same

 

[tucktuck8]

Thank you guys!

 

[SI2IS2T4R]

hmmm...

The video didn't show up on Tapatalk, but it did in regular web viewing. Kinda hard to decipher the sounds. I do hear beeping.

But, this brings up a question.... I commonly approach my parking spot at home which requires me to crawl/drive over an 6-8 inch curb. I usually take it pretty slowly, not to bounce every one around in the vehicle. And sometimes, the vehicle makes this grinding sound going up the bump. I always thought it was the traction control kicking in for whatever reason, but would it be this so called "hill assist"?

Alright so i've posted about this before but had a tough time explaining the noise. When I'm on a steep incline and let off the gas I roll back, as I'm rolling back I press the accelerator and it makes this noise until I am moving forward. Also, At no point does the "hill start assist" stop my car from rolling backwards. It doesn't sound like a normal noise a car should make. Imagine if you were to flick one of those door stop springs. sounds like that. Anyway I have a video of it happening.

It made this same noise when I was butted up against a curb going forward and I hit the gas to crawl over it.


Turn volume up
<iframe width="420" height="315" src="//www.youtube.com/embed/ABfEcyX8klI" frameborder="0" allowfullscreen></iframe>

first time posting a video let me know if it shows up.

 

[m85476585]

The video didn't show up on Tapatalk, but it did in regular web viewing. Kinda hard to decipher the sounds. I do hear beeping.

But, this brings up a question.... I commonly approach my parking spot at home which requires me to crawl/drive over an 6-8 inch curb. I usually take it pretty slowly, not to bounce every one around in the vehicle. And sometimes, the vehicle makes this grinding sound going up the bump. I always thought it was the traction control kicking in for whatever reason, but would it be this so called "hill assist"?

That's probably traction control keeping one or more of the wheels from spinning. If you don't hit the curb straight on, one or more of the wheels might be in the air momentarily. Since you are crawling up there is a lot of drive force on the tires and it's easy to lose traction on one for a moment. A little gravel under one of the tires could be enough to cause it to slip a little. Or one of the tires could slip as it goes up the curb. Traction control will apply the brakes (loudly) to keep the power going to the wheels with good traction.

Hill assist control is meant to keep you from rolling backwards on hills, but I don't think I've seen it work. I usually end up keeping my other foot on the brake until I get going on the gas if it's steep.

Downhill assist control (The DAC button) uses the traction control/ABS system to help you crawl down a hill, and it's also really loud in use since it pulses the brakes the same way (but in irregular bursts). It only works in 4L, and it works best with the shifter in 2 or L.

We have one of the most versatile but rugged 4WD systems out there. It's just a little noisy in some of the modes.

 

[tucktuck8]

so m854 you would say the twanging in the video is normal too?

 

[SSt4r]

The beeping is letting you know it's working (hill start assist, DAC, VSC, etc.) and the vibrating noise is the brakes being applied. All sounds normal.

 

[m85476585]

so m854 you would say the twanging in the video is normal too?

It's hard to tell from the video. I don't think I've ever experienced the hill assist feature. The times I might have needed it, it didn't react soon enough so I applied the brakes manually. I suspect it doesn't activate until it detects you rolling back, and the wheel speed sensors don't seem to work well at extremely low speed, so you have to get some backwards momentum before it kicks in. I would expect it to stop the vehicle, but maybe it doesn't work as advertised? A more logical system would be to hold the brakes until you press the gas.

See if you can test out DAC. It's the same system that controls all these things (HAC, DAC, VSC, TCS, auto LSD for 2WD), and DAC is a good way to manually activate it. See my last post for how to start it. DAC will attempt to keep your speed between 2-4mph, so you might need a fairly steep hill to make sure it's working. On difficult terrain, 2-4mph can feel way too fast!

 

[radlynx]

that's definitely your hill assist control. the purpose of that is so you can have time to move your foot from the brake to the gas and not roll backward. if you wait a couple more seconds and don't press the gas, it will still roll backward and will make that sound. it will not hold the car for too long for you, you will need to press the gas for that.

I used to have that problem and noticed that when i adjusted my parking brake to specification, it stopped rolling backwards. you should only hear around 8 clicks to fully hold the car. if it's more than that, you will need it adjusted to specs.

 

[Cornelius]

Mine makes the exact same noises I hear in your clip -- the clicking and the dinging...as it's rolling backwards.

There was a thread on here recently where a bunch of folks chimed in about whether or not theirs would hold the car on an incline. Most (including myself) said that it wouldn't even hold the car for a few seconds, as it is advertised to do.

I don't think it's the parking brake adjustment, though. The parking brake is a manual, cable-operated deal. The hill assist is using the actual ABS system to hold the vehicle. In my opinion, it's just a flawed execution of a great idea, and probably won't work in anything but a gradual suburban driveway.

And from what I've heard (again, from these forums), the Downhill Assist Control actually works very, very well. It's just the hill start that is absolute garbage. So testing one won't necessarily give you an idea if the other is working. They're both totally independent.

 

[m85476585]

Mine makes the exact same noises I hear in your clip -- the clicking and the dinging...as it's rolling backwards.

There was a thread on here recently where a bunch of folks chimed in about whether or not theirs would hold the car on an incline. Most (including myself) said that it wouldn't even hold the car for a few seconds, as it is advertised to do.

I don't think it's the parking brake adjustment, though. The parking brake is a manual, cable-operated deal. The hill assist is using the actual ABS system to hold the vehicle. In my opinion, it's just a flawed execution of a great idea, and probably won't work in anything but a gradual suburban driveway.

And from what I've heard (again, from these forums), the Downhill Assist Control actually works very, very well. It's just the hill start that is absolute garbage. So testing one won't necessarily give you an idea if the other is working. They're both totally independent.

Well, at least testing DAC will test if the ABS system is working since it applies the brakes the same way.

 

[BlackWorksInc]

HAC will only apply the brakes for a short amount of time (as it basically is 100% duty cycle and anymore than a few seconds could damage the unit.) I've never had it actually "hold" the 4Runner, but it does seem to slow the rate at which it rolls backwards. I would assume if I gave it enough time that it might actually stop the vehicle from rolling backwards completely for a short while?

HAC in the 4th gens is sort of finicky in my experience, its not a bad concept but I've rarely had it kick in on San Francisco hills and/or off-roading so there is a "trick"I assume to making it kick in properly. This might be so it doesn't always activate every time you're on an incline? One of these days I may bother looking it up in the owner's manual or TIS, but its honestly never mattered enough for me.

Those are all noises that are normal for HAC when it is kicking in. If you think that's bad, wait until ATRAC kicks in or your use DAC on a big Hill, the 4Runner will sound like it wants to blow up! It can be pretty disconcerting.

 

[robtmc]

If you think that's bad, wait until ATRAC kicks in or your use DAC on a big Hill, the 4Runner will sound like it wants to blow up! It can be pretty disconcerting.

+1

I tried out DAC the other day on a steep hill since I had stopped to switch to 4Lo. It does sound like the truck is tearing itself apart!

 

[m85476585]

I found a small hill to test HAC today, and I can confirm it's a useless feature. It sounded just like the video, with fast pulsing brakes and beeping. It let me roll back a bit (faster than I would prefer to roll back), then it came on and brought the truck to a stop for a second, then let me roll back again, then stopped it again. I guess it might be enough to keep you from going too fast backwards, but you'd have to really not be paying attention for it to help.

I didn't do anything special to activate it. I just came to a stop on a hill in drive, then let my foot off the brake and rolled backwards. I didn't test whether there are any conditions that cause it not to activate.

 

[m85476585]

I had HAC kick in on a trail today. I came to a stop with one of the front wheels partly up a large rock. I stopped to lock the center since it was having trouble unlocked, and I wanted to crawl up it. It wouldn't lock, so I let the truck roll backwards to realign things, and HAC quickly came on since the rock was short but steep. It didn't stop me, though, it just slowed me down, kind of like DAC in reverse.

 

[Farzad_K]

I own a 2016 T4R and get this on a slope which is not very steep at the entry gate to my condominium community waiting for gate to open. When gate is ope enough I let go of the break and by the time I am able to reach the throttle the car is already rolling back. As soon as I push the tthottle down it makes that noise and a yellow light comes on in the instrument panel. It is not a very steep slope. Should I take it to a dealer for inspection? It only has 500 miles on it.

 

[techno]

What you are describing sounds exactly like the Hill Start Assist system that we have on the 4th gens (03-09), so I would assume everything is working as it should. The noise is the ABS controller doing stuff with the brakes to prevent/reduce rollback, and the light is simply telling you that it's doing something automatically.
It doesn't need to go to the dealer, but if you're still unsure, I suggest asking this question in the 5th gen (10-16) subforum.

 

[bko4488]

The YouTube link in the OP is no longer working but I think I experienced the same thing in my '06 today pulling out of a public parking lot with an incline driveway. There weren't any beeps though — just clicks.

Thankful to find this thread since I was fearing the worst. Thought it might be the transmission.

 

[pnwcruiser]

The YouTube link in the OP is no longer working but I think I experienced the same thing in my '06 today pulling out of a public parking lot with an incline driveway. There weren't any beeps though — just clicks.

Thankful to find this thread since I was fearing the worst. Thought it might be the transmission.

We've owned our 2005 4Runner since new, sounds normal to me. On steep inclines, after being at a dead stop with foot applied to brake pedal, as I move my foot from brake to accelerator pedal it will make the rapid clicking sound. This is the brakes applying (it's using ABS system to apply brakes, same sound when you slam on the brakes and ABS kicks in). If it's for more than about 2 seconds, it'll beep too. You'll notice the traction control light come on in the dash at that point too. Once you start accelerating forward, the system is back to normal and traction control light will be off. If you hear the noises and your 4Runner continues to roll backwards, you might have a problem. Test that without anyone behind you.