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Ability to add Hill Decent?

EXSlider400
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EXSlider400 Senior Enthusiast

EXSlider400

Posted
Posted

I have had a few z71 Denali 4WD trucks but with the 2019 Denali Ultimate Yukon it does not have hill decent. I don’t think Z71 was an option on this trim Yukon. Why I don’t know...even the Acadia I rented this week had hill decent and it is not even a z71. Anyway, I know it modulates the ABS individually by wheel and I have had to use this in ice situations when going down hill in a curve and worked great every time... passing by other vehicles in the ditch. 

 

Has anyone tried to add it? Sometimes the pigtail is already there like the old DIC on the 07-13 trucks. Before I remove the dash, has anyone noticed if the pigtail is there? If so I can buy the button cluster from a Z71 Tahoe and try it.  I don’t know if a re-flash would be required either. 

SARNCAN Enthusiast

SARNCAN

Posted
Posted
I have had a few z71 Denali 4WD trucks but with the 2019 Denali Ultimate Yukon it does not have hill decent. I don’t think Z71 was an option on this trim Yukon. Why I don’t know...even the Acadia I rented this week had hill decent and it is not even a z71. Anyway, I know it modulates the ABS individually by wheel and I have had to use this in ice situations when going down hill in a curve and worked great every time... passing by other vehicles in the ditch. 
 
Has anyone tried to add it? Sometimes the pigtail is already there like the old DIC on the 07-13 trucks. Before I remove the dash, has anyone noticed if the pigtail is there? If so I can buy the button cluster from a Z71 Tahoe and try it.  I don’t know if a re-flash would be required either. 


The problem with the Denali is they replaced the Hill Decent knob with the retractable power-step knob, but I don’t know if the system can still be activated on other way or not!
EXSlider400 Senior Enthusiast

EXSlider400

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Posted (edited)

You are right... now how do I remove that trim to look for an extra pigtail and to see it it is an individual button or as a cluster group. 

 

I will never need to disable the running board so I don’t mind removing that button. 

 

The Yukon Manual mentions Hill Decent button... but I have not seen any offer it other than Tahoe (for this platform). 

 

 

CEE92669-2BB0-4694-B3DF-202E55F958B0.jpeg

AA7395AD-599D-48E5-AAC6-91B62ECFA8F5.jpeg

Edited by EXSlider400
  • Like 1
EXSlider400 Senior Enthusiast

EXSlider400

Posted
  • Author
Posted (edited)

Here is the Z71 switch:

 

To remove the switch trim/housing on the dash, it looks like it should just be snap in tabs but before I try it, I would like to know if anyone else already knows before I damage it. 

 

https://www.gmpartsdirect.com/oem-parts/gm-tract-control-switch-23172141/?c=Zz1lbGVjdHJpY2FsJnM9c3dpdGNoZXMmaT1HQTE1MzgwNSZyPTcmYT1jaGV2cm9sZXQmbz10YWhvZSZ5PTIwMTcmdD1wcmVtaWVyJmU9NS0zbC12OC1mbGV4

 

 

 

 

264563C4-0378-46C8-9287-2C8170ABBA33.jpeg

Edited by EXSlider400
SARNCAN Enthusiast

SARNCAN

Posted
Posted
You are right... now how do I remove that trim to look for an extra pigtail and to see it it is an individual button or as a cluster group.   

I will never need to disable the running board so I don’t mind removing that button. 

 

 

CEE92669-2BB0-4694-B3DF-202E55F958B0.jpeg.9f05f06346f80d8228d0847d72720ea1.jpeg

AA7395AD-599D-48E5-AAC6-91B62ECFA8F5.thumb.jpeg.f9b064943eafeb13d517622ccda657cc.jpeg

 

 

I guess it is not only to disable the running board, but also to keep it open when needed like washing the car. It functions as a hold to the running board rather than disabling I guess.

 

  • 2 weeks later...
Gmman Enthusiast

Gmman

Posted
Posted

I added the switch when I found the wires. I don't think the BCM is programed. Can HILL DECENT be programed in?

EXSlider400 Senior Enthusiast

EXSlider400

Posted
  • Author
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I don’t see why they would not be able to.  The vehicle already has the information for the degrees of center. I guess we need a technician to comment. I know my 2007 did not come with cruise control and I had them program it in after I added the parts. 

  • Like 1
  • 3 weeks later...
cmatt Enthusiast

cmatt

Posted
Posted

It appears your vehicle may already have it...or what it’s evolved to - Powertrain grade braking.

105223d34b34ba0ef3328de3acd484d8.jpg


Sent from my iPad using Tapatalk

EXSlider400 Senior Enthusiast

EXSlider400

Posted
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Posted

Grade breaking is not the same as hill decent but they may share some of the same features. 

 

I stoped this mod as I am trying to get a buy back because of the cabin pressure issue. 

Gmman Enthusiast

Gmman

Posted
Posted

Grade breaking is different. I would like to keep this going. I would still like to find out if it can be programed in. Could mister White chime in on this? 

SARNCAN Enthusiast

SARNCAN

Posted
Posted

I just have found out that this feature is listed at the RPO vehicle’s codes sticker. Look for it

(JHD) HILL DESCENT, GEAR HOLD

EXSlider400 Senior Enthusiast

EXSlider400

Posted
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Posted

That sounds similar but different. It sounds like grade braking since it mentions “gears” because hill decent just modulates individual brake calipers. This sounds like when descending a mountain or hill at normal speeds it will keep the vehicle from speeding up (I forgot what this was called but I remember it activates after tapping the brake twice or something like that). Does anyone know of a Z71 RPO that specifies “hill decent”. I will see what mine says. 

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