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HSA

silveradosid

By silveradosid
in Engines & Drivetrain

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silveradosid Senior Enthusiast

silveradosid

Posted
Posted

after reading the manual about hill start assist, I have discovered mine doesn't work. my driveway is about a 4 degree incline, when I pull into the driveway and want to inch my way in HSA will display on dic but the truck will keep rolling backwards unless I give it gas. then the truck will lurch forward and I have to hit the brake. if I let off the brake I get the same thing with HSA and the truck rolls backwards. do you think this is a transmission problem.

MikeNH Senior Enthusiast

MikeNH

Posted
Posted

HSA is not at all connected to the transmission. HSA just applies the brakes and will only do so for about two seconds according to the manual. Are you rolling backward instantly or does it take a moment for it to start?

 

Also, HSA will only engage once per stop. So if you're crawling in a stop and go sort of fashion, it will not engage every time.

1300c Enthusiast

1300c

Posted
Posted

You'll also notice it's working if you let of the brake, and instead of hitting the gas, press the brake pedal again. You'll notice a much firmer pedal akin to when you pump the brake pedal when the truck is off.

Rawyzf Senior Enthusiast

Rawyzf

Posted
Posted

Health Savings Account comes to mind.

 

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TJay74 Senior Enthusiast

TJay74

Posted
Posted

It only holds for a couple of seconds as someone stated earlier. It is designed to hold the truck as you transition from the brake pedal to the gas pedal so the truck doesn't roll backwards during the transition.

Zachlovesfood Enthusiast

Zachlovesfood

Posted
Posted

Have to make sure you come to a complete stop before letting off the brake.

I've also been wondering if leveling/lift kits adjust how the truck determines its angle. Since they come stock with 3-4" of rake, being on a 4 degree incline might make it think it's close to level. Stock rake might make the truck think it's going downhill all the time, which is why people complain about grade braking...

Anyway, wish I had tested with it stock height. But every incline I come to, I come to a complete stop. The truck will stay stopped until I press on the gas. It has never released on its own before, and I've waited for 60+ seconds due to traffic.

The message pops up on the DIC for a few seconds before going away.

 

 

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silveradosid Senior Enthusiast

silveradosid

Posted
  • Author
Posted

i do have 1.5 lift in front, i tried again last night. i pulled in my driveway and used the brake to bring the truck to a complete stop and when i let my foot off the brake pedal the truck will start rolling back out the driveway.

TJay74 Senior Enthusiast

TJay74

Posted
Posted

I believe you have to pump the brake 2 or 3 times for it to enact the HSA program.

MikeNH Senior Enthusiast

MikeNH

Posted
Posted

I believe you have to pump the brake 2 or 3 times for it to enact the HSA program.

Nope.

Zachlovesfood Enthusiast

Zachlovesfood

Posted
Posted

i do have 1.5 lift in front, i tried again last night. i pulled in my driveway and used the brake to bring the truck to a complete stop and when i let my foot off the brake pedal the truck will start rolling back out the driveway.

That's extremely odd, especially if it's popping up on the DIC telling you that it's active. Maybe try to find a taller incline, experiment around? If not, perhaps resetting the computer (disconnecting the battery for 30 minutes or so) will help. Can't hurt to try. Let us know if you find anything else out!

 

 

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  • 2 weeks later...
redwngr Senior Enthusiast

redwngr

Posted
Posted
During the transition period between when you release the brake pedal and start to accelerate to drive off on a grade, HSA holds the braking pressure for a maximum of two seconds to ensure that there is no rolling.


The brakes will automatically release when the accelerator pedal is applied within the two-second window.

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