Intermittent Intellitrak & ABS warning lights

[Evan Sanders]

Hi all, first post here so please excuse any FNG stupidity (I tried searching for this but not a ton of luck finding actual solutions).  I have a 2009 Suburban that the cruise stopped working on a few years ago.  I don't use it much so I never did anything about it.  Recently I'm starting to get warning lights that Intellitrak and ABS need service, usually this happens only on colder mornings (California cold, so like 50 degrees or so).  Also recently I've started having an issue with the park interlock not letting the truck shift out of park, again usually on cold starts and very rarely when the truck is warm.  I have a feeling that there's a common sensor that these systems use that is causing all or most of these failures, and am hoping that someone can help me narrow down where to look without having to jiggle every electrical connection at every wheel to try to figure out which one might be the culprit.  Can anyone loan me a clue? 

 

I've had this truck since 2010 and have done all the maintenance and repairs on it myself.  It's in great shape for having been through 5 kids and I'm starting the process to get it more suited towards light four wheeling for the purpose of getting my wife and I to remote trailheads so we can backpack deeper in the wilderness.  Step one is to take care of these things that effect safety and drivability, step two will be to fix random things that never bothered me enough to fix until now just to get the truck to 100% before I start in on the fun stuff.

Edited September 14, 2020 by Evan Sanders

[MaverickZ71]

Too many possibilities.  Almost any trouble code can throw a Stabilitrak/ABS warning, even it the problem has nothing directly to do with Stabilitrak/ABS.  You need to get the codes read.  It could very well be the shifter safety interlock.  Some auto parts places will scan codes for you for free (because they want to sell you the subsequent parts).  Or if you subscribe to OnStar, press the blue button and tell them you want a remote diagnostic run and for them to tell you the code number(s).  Then you can look the code number up on the internet to see what the common fix is.  Last resort is to bite the bullet and pay the GM dealer $100+ per hour for an initial diagnosis.  

Edited September 14, 2020 by MaverickZ71

[Evan Sanders]

Yeah I was a little premature posting this, I have a code reader and just haven't hooked it up yet.  Hoping for the easy answer I suppose.

[ecard_926]

I had this same thing happen to me. Didn't notice the shifting into gear problem, but everything else is what I had. Mine was the switch on the brake pedal. Solved everything. I can see that being the problem with the shifting out of park issue as well. Hope this helps.

Sent from my SM-G930T using Tapatalk

[MaverickZ71]

I had to replace the brake light switch on our '09 Silverado because the cruise control quit working.  Crazy thing is, the brake lights still worked and it shifted in and out of park perfectly.  

 

I've also seen the Stabilitrak/ABS lights and chime accompany bad throttle body codes, AFM misfire codes, low brake fluid codes, etc.

 

The problem is, it seems like the cheaper code readers will read most of the powertrain error codes, but when you get into some deeper electrical issues or body control module codes, etc, you have to have an expensive GM scantool to read those.    

[newdude]

I'd have the codes read to really see what is going on, but cruise not working and not coming out of park could be caused by the brake pedal position sensor.  The sensor is related to cruise control as that is one of a couple options that cancels the cruise control.  As for the coming out of park, that sensor is used by the Body Control Module and Engine Control Module to see if the pedal has been applied or not in order for the BCM to then power the shift interlock solenoid and let you shift out of park.  

[newdude]

42 minutes ago, MaverickZ71 said:

I had to replace the brake light switch on our '09 Silverado because the cruise control quit working.  Crazy thing is, the brake lights still worked and it shifted in and out of park perfectly.  

 

I've also seen the Stabilitrak/ABS lights and chime accompany bad throttle body codes, AFM misfire codes, low brake fluid codes, etc.

 

The problem is, it seems like the cheaper code readers will read most of the powertrain error codes, but when you get into some deeper electrical issues or body control module codes, etc, you have to have an expensive GM scantool to read those.    

 

Blue Driver.  https://www.bluedriver.com/products/bluedriver-scan-tool

 

They have what they call "enhanced diagnostics" that can read ALL the OBDII codes in ALL the modules it can find for many brands, including GM.  I have two of these and they will read all modules, from ECM and TCM to BCM and HMI and more.   

Edited September 14, 2020 by newdude