Truck rolls backwards in Drive......why?

[ToyotaTrk]

Sounds like many are not activating the hill start assist properly? Are you mashing the pedal hard to getting the chime/dash notification?

How do you activate it? Page 366 states its activated automatically when the foot is taken off the brake. I recently had a chance to check it out while trail climbing in NC - I just roll backwards and get a loud clicking noise... Has anyone actually used the feature? Im guessing its only for railroad crossings or not very steep inclines, etc as I dont roll backwards then but then that doesnt explain the garage situation mentioned earlier here unless its a really steep one.

1. ■ Hill-start assist control is operational when●The shift lever is in D or S.
   ●The brake pedal is not depressed.

 

[risban]

How do you activate it? Page 366 states its activated automatically when the foot is taken off the brake. I recently had a chance to check it out while trail climbing in NC - I just roll backwards and get a loud clicking noise... Has anyone actually used the feature? Im guessing its only for railroad crossings or not very steep inclines, etc as I dont roll backwards then but then that doesnt explain the garage situation mentioned earlier here unless its a really steep one.

1. ■ Hill-start assist control is operational when●The shift lever is in D or S.
   ●The brake pedal is not depressed.

I am wondering the same for my 2014 LX.....how is it activated? While the gear selector is in D or S, do you simply mash on the brake pedal for 3 seconds for it to activate?

The Lexus manual is quite vague about this feature.

 

[bloc]

It should always be on. Activates when you are rolling backwards with the transmission in drive. I'm not sure if there is a difference in operation when you have your foot on the brake or not. I just know if I'm on a hill and not giving it enough throttle to sit still or go forward my 13 starts doing its thing.

The loud clicking ToyotaTrk mentioned is the ABS/stability module activating the brakes to get it to stop rolling backward.

 

[Terry Ivanov]

Hill Start assist is only activated while Engine is running, as soon as you kick it back to "P" and turn the engine OFF and release the brakes Transmission LOCK activates locking your transmission in place. Depending on the incline it rolls back or forward just a bit. Every single vehicle does it, on LC's it's a bit more noticeable because of the weight and the way transmission lock is built. The parking brake will solve all of your issues. Spring Sound and jittering that is you Traction Control trying to figure out what the hell is going on. Very typical Toyota thing, let is be It's Toyota, they know what their doing

 

[risban]

I took my 14 LX for service today and went for a drive with a senior tech to show me Hill Start Assist. On a noticeable incline with transmission in D, he lifted his foot from the brake pedal, the vechicle momentarily held and then started rolling back. The ABS and whatever other electronics chattered away but kept rolling back.

He said the system is NOT designed to keep the vehicle stationary for an indefinite period time. But just long enough to move your foot from the brake to the gas pedal to get moving forward without rollback.

Having trouble buying that.....sound right?

 

[Hatteras]

He said the system is NOT designed to keep the vehicle stationary for an indefinite period time. But just long enough to move your foot from the brake to the gas pedal to get moving forward without rollback.

Having trouble buying that.....sound right?

He is right. That is the way I understand (and observe) my 13 LC also works.

 

[Angelo1]

Porsche does this is as well.

 

[Cruisin911]

Given a steep enough slope and if you let the LC roll back a few feet, when you do move to press the gas, it'll likely stall. My tundra did the same thing and i first noticed it on a steep slope with a trailer. I can see how someone would get annoyed by this, specifically if they lived somewhere in San Fran. However, it would appear that it takes a little time to get used to this and to stop the behavior completely. The transmission expects to move forward in Drive. This is where your traction control goes haywire.

Porsche does this? Who buys an automatic Porsche? (SUVs excluded) My manual 993 doesn't have hill hold. My 2018 VW Alltrack has it. I think most manuals after 2012 or so likely have some form of it. Subaru had it on their manuals for quite some time.....

 

[ElJayBird]

I’ve just accepted that my LC doesn’t have hill assist. I know Toyota claims it does but functionally, it does not. So i use both feet on hills.

My Mercedes has hill assist. When I’m on a steep incline and remove my foot from the brake, it stays put.

 

[waybigdog]

On my 2020 LC here is what I have experienced.
We live on a steep driveway, how steep is it you ask ? I don't know but its steep.
The garage is at the top and to the side there are 2 level spaces to turn left into.
If I stop and then proceed to take my foot off the brake to go straight ahead to the garage, I roll back.
If I stop and turn the wheel to go left into the space and release to pull into the space, I do not roll back at all.

 

[Ruquik]

The magic of the torque converter really mystifies the general public, LOL

 

[Devil's Slide Doug]

Do you have two feet? When they taught you to drive and told you to only use one foot they were wrong. Left foot on Brake, Right foot on accelerator! it works when I'm rock crawling, It works when I'm driving a forklift, It should work with a Land Cruiser on the street on a steep hill.

 

[Markuson]

The first 100 years of automobiles are shaking their heads at this conversation…

 

[Heckraiser]

I love the video of the classy lady in her business suit trundling through the Utah wilderness

 

[manofthewoods]

Do you have two feet? When they taught you to drive and told you to only use one foot they were wrong. Left foot on Brake, Right foot on accelerator! it works when I'm rock crawling, It works when I'm driving a forklift, It should work with a Land Cruiser on the street on a steep hill.

How my dad always drives.
I have a manual Taco, I can't tell you what foot does what, they just do it

 

[TeCKis300]

My driveway is sloped, yesterday I performed a little test, with the truck in D I took my foot off the brake, the thing will roll down a hill until you add gas. When you add gas it makes the hideous noises as the hill start assist kicks in. I've never owned an automatic transmission that behaves this way. If i do the same thing in my LX470 the truck stays put, no rolling. I know this is normal behavior, I'm just wondering if anyone here knows why it was designed this way. It's a 2015 LX.

Thanks

This is a normal feature of the car. For some reason, it sounds to me like the system in your particular vehicle is over-active?

I would look into zero-point calibration of the vehicles accelerometers. It's one of the primary sensors that the vehicle uses for a host of traction and stability control features. It should be done anytime the vehicle is serviced for suspension or alignment, and is something often missed by many.

Zero Point Calibration

forum.ih8mud.com

 

[loop737]

This is a normal feature of the car. For some reason, it sounds to me like the system in your particular vehicle is over-active?

I would look into zero-point calibration of the vehicles accelerometers. It's one of the primary sensors that the vehicle uses for a host of traction and stability control features. It should be done anytime the vehicle is serviced for suspension or alignment, and is something often missed by many.

Zero Point Calibration

forum.ih8mud.com

Thanks for the info, the truck's long gone. For some reason, although a great vehicle, the 200 just never put the hook in me......still have the 06 LX though.

 

[Leelanau]

Gotta love a good post resurrection!

 

[rscoleman]

On a side Note. My favorite thing to do in my manual transmission T100 is allow it to roll backwards at an incline stop light. It freaks out people behind me, it annoys the hell out of my wife if she is passenger. It is just plain old fun.
Back on topic have not noticed the 2016 LC making any odd noises or noticed it rolling back on steep inclines. I do notice it roll back a tiny bit when I pulling out from boat ramp with boat and trailer attached but even then still no noises.

 

[Beej1337]

It should always be on. Activates when you are rolling backwards with the transmission in drive. I'm not sure if there is a difference in operation when you have your foot on the brake or not. I just know if I'm on a hill and not giving it enough throttle to sit still or go forward my 13 starts doing its thing.

The loud clicking ToyotaTrk mentioned is the ABS/stability module activating the brakes to get it to stop rolling backward.

Mine started doing this, it does not hold the vehicle, this never use to be a problem, the vehicle use to hold without crazy clicking noises. Has anyone had this fixed?