Engine Stall with Hill Assist

[pcstockton]

Hello all!

I am not exactly sure what to call the "feature" that keeps you from backing down a hill when stopped and you take your foot off the brake? Hill Assist? I hate it.

I was driving up a snowy/icy hill. I hit a patch and my truck slowed to a stop. The hill assist kicked in, and suddenly I am careening backwards down the hill. Brakes not working and steering not really working.

Luckily I slid straight down the hill with cars parked on both sides, and hit nothing! Miracle.

Once I was at the bottom I noticed the engine was completely off. It stalled out, hence the lack of brakes and steering.

Is this normal?

I instantly started heading backwards down the hill when the truck came to a stop. I didn't have time to, nor would I have, turned the key off and back on?!?!?!

It scared the crap out of me.

Does anyone have an explanation? Is something wrong? Or was it just a fluke occurrence?

Thanks!

 

[CutthroatSlam]

How many miles on the rig? Brakes should continue to work manually, but not certain that would have been much help in those conditions.

 

[El Dusty]

Does anyone have an explanation? Is something wrong? Or was it just a fluke occurrence?

Thanks!

As far as hill start assist. It exists but it is more of a passive system and not a lot of users have reported good results. When you release the brakes and start rolling backwards it pulses your brakes similar to abs to slow your reverse roll down and gives you a few seconds to get back on the gas to get going again.

From another user "Playing with it one time, I let it continue to roll back after the noise quit and it kept rolling until the brakes or transmission stopped it hard and killed the engine. Won't do that again. As others said "scared the crap out of me"

See other thread, Hill Start Assist Control - is it not working, or just a badly implemented idea?

In your case if you didn't have enough traction to continue the drive up the hill there is little chance you ever would have been able to release the brakes from a stop and get started uphill at that point. Maybe time for new tires or snow tires? :smow:

 

[pcstockton]

130K. Brakes were just inspected.

 

[pcstockton]

As far as hill start assist. It exists but it is more of a passive system and not a lot of users have reported good results. When you release the brakes and start rolling backwards it pulses your brakes similar to abs to slow your reverse roll down and gives you a few seconds to get back on the gas to get going again.

From another user "Playing with it one time, I let it continue to roll back after the noise quit and it kept rolling until the brakes or transmission stopped it hard and killed the engine. Won't do that again. As others said "scared the crap out of me"

See other thread, Hill Start Assist Control - is it not working, or just a badly implemented idea?



In your case if you didn't have enough traction to continue the drive up the hill there is little chance you ever would have been able to release the brakes from a stop and get started uphill at that point. Maybe time for new tires or snow tires? :smow:

Thanks!

Thats the thing. It happened so fast I couldn't get on the brakes before it stalled.

It was not so steep or slippery that my brakes wouldn't have held me.

Brand new KO2S.

 

[03_4x4Runner]

I had something similar on my 2014 several years ago. My driveway is steep. I was part way up the driveway and decided to check the mail. I decided to just coast back down the driveway a little but left it in drive. It went a few feet and buzzer started going off. I do not remember if it completely stalled but it was not happy about it. Bottom line is do not try to coast backwards with the trans in drive. Shift to reverse.

 

[Bmnorm2]

Hello all!

I am not exactly sure what to call the "feature" that keeps you from backing down a hill when stopped and you take your foot off the brake? Hill Assist? I hate it.

I was driving up a snowy/icy hill. I hit a patch and my truck slowed to a stop. The hill assist kicked in, and suddenly I am careening backwards down the hill. Brakes not working and steering not really working. I think this feature is designed to work when you come to a stop using the brakes. If you accelerate up a hill and then left off the accelerator and let the vehicle lose forward momentum and then start rolling backwards while never bringing it to a stop with the brakes the system isn’t intended for this scenario.

Luckily I slid straight down the hill with cars parked on both sides, and hit nothing! Miracle.

Once I was at the bottom I noticed the engine was completely off. It stalled out, hence the lack of brakes and steering.

Is this normal?

I instantly started heading backwards down the hill when the truck came to a stop. I didn't have time to, nor would I have, turned the key off and back on?!?!?!

It scared the crap out of me.

Does anyone have an explanation? Is something wrong? Or was it just a fluke occurrence?

Thanks!

Tested the Hill Start feature on my ‘21 Nightshade (limited) today and it worked flawlessly. Stopped on a solid 20% grade, let off the brake pedal without touching accelerator and the vehicle didn’t move an inch.

Will try on steeper grade when the opportunity arises.

It sounds like your tires actually slid in this instance.