Jump to content

Service Brake System Message...

Mark Francois
 Share

Recommended Posts

Mark Francois Enthusiast

Mark Francois

Posted
Posted

I've been getting an intermittent Service Brake System Message along with the ABS light and Parking Brake warning light on my 2003 GMC Yukon 2wd with the 4.8l motor. Sometimes it will be days or a week or two between getting the message or maybe one day to the next but they always clear up after I drive a little, stop and restart the truck,. Sometimes it is as quick as just driving just a couple hundred feet and restarting the truck or it may be when I reach my destination. I'm hoping that it is just an intermittent failure from one of the front ABS sensor but is there a way to check the sensors out with a multimeter to make certain that it is them or just a way to trouble shoot the system in general. It is kind of a tough one since it is an intermittent issue. Thanks in advance!

 

IMG_2606[3350].jpg

makingterrificdecisions New Member

makingterrificdecisions

Posted
Posted

I've got simlilar message. Service brake booster. Read up on it and it could be many things including:

- replace brake booster or vacuum pump (wasn't for a silverado though)

- poor contact of the sensor due to rust/corrosion

I can't remember the last one, but best to take it to a mechanic because it seems pretty random

 

  • Like 1
davester Senior Enthusiast

davester

Posted
Posted

It's also common for the ground connection to be a problem for the abs computer.  It's located on the wing, just off the frame under the driver's seat.  Unbolt the wires from the wing, clean the connectors and the wing, bolt them back down and smear some dielectric grease over them.

  • Like 1
Mark Francois Enthusiast

Mark Francois

Posted
  • Author
Posted (edited)

Thanks guys, I'm guessing that you mean these two grounds attached to the body mount perch under the drivers footwell just behind the front wheelwell? If so, I'll clean them up and put some DI grease on them this weekend.

 

IMG_2628.jpg

Edited by Mark Francois
added picture
Mark Francois Enthusiast

Mark Francois

Posted
  • Author
Posted
18 hours ago, davester said:

Yup, those are the ones.

Cool deal! I’ll try what you suggested this weekend. Thanks. 

Mark Francois Enthusiast

Mark Francois

Posted
  • Author
Posted (edited)

Well, the grounds were not the issue so I got off my lazy butt and tested the sensors themselves. What I found was that the passenger side sensor output was half the voltage (AC) of the drivers side. I belive that testing the sensor with a multimeter on AC while spining the tire is the proper way to check function. I know that the rate in which I spun each wheel was not exact betwen the two but it wasnt so much of a difference that the voltage should differ by half. What do you guys think? Something else I noticed while troubleshooting this issue is that when not in alarm, unplugging the drivers side sensor only illuminated the abs light but when unplugging the passenger side sensor tripped the abs and brake icons in the dash. Is this the intent to help mechanics differentiate between faulty sides or am I seeing something else and don’t realize it?

Edited by Mark Francois
  • 2 weeks later...
Mark Francois Enthusiast

Mark Francois

Posted
  • Author
Posted

Well, changing out the front two abs wheel sensors didn't fix the issue. At first it seemed right but then it lot up again then it was off and then it was on again lol I didnt mind the work it took to swap those out but dang I’m tired of this intermittent problem garbage!  

  • 2 months later...

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
 Share
Go to topic listing

  • Recently Browsing   0 members

    • No registered users viewing this page.

  • Forum Statistics

    250.4k
    Total Topics
    2.7m
    Total Posts

  • Member Statistics

    342,840
    Total Members
    8,960
    Most Online
    appletrav
    Newest Member
    appletrav
    Joined

  • Who's Online   1 Member, 0 Anonymous, 501 Guests (See full list)

  • Latest Articles

  • Posts

    • newdude
      2 speed transfer case optional now?

      By newdude · Posted

      This is a 1/2 ton thing ONLY.  All HDs 2020-2026 have the two speed transfer case, with Autotrac as an option.     1/2 tons 2019-2026, regular 4x4s come with a single speed case (no 4LO!), and trucks with Z71 ordered, or all Trail Boss trucks come with the 2 speed case.  2 speed case is also an option on WT, and is also standard on High Country.  
    • newdude
      Different requirements for oil filters?

      By newdude · Posted

      2013 5.3 still to this day calls for the PF48 filter.  Which as a 15psi bypass pressure.     There is a TSB, 17-NA-157 that talks about the PF-63 and PF-64 filters which have a higher bypass rating of 22psi.    TSB HERE - temp.xml   "Beginning in 2012, the oil pumps began to regulate main gallery feedback instead of pump out pressure. This means that the oil pump now does not begin to regulate until pressure is built up to the main gallery. This change reduces the amount of time it takes to provide oil to the engine bearing and lifters during extreme cold start conditions.  Main gallery feedback oil pump control systems are present on the following engine families which use Spin-on oil filters: Small Gas Engine (SGE), Large Gas Engine (LGE), High Feature (HFV6) Gen2 and Small Block Gen5 gasoline engines. These engines with the main gallery feedback oil pump control systems are factory built with an ACDelco® oil filters"   It also calls out what engines use those filters.  The gen 4 small blocks were not on that list (LMG, LC9, L9H, L92, L94, L20, L96).  Gen 5 small blocks use the higher pressure filter.          That all said...   Your 7045 Napa filter is the PF63 equivalent, with 22psi bypass.  You are already using the higher bypass pressure filter.  You CAN keep using it, you don't technically have to use it though.  
    • Grumpy Bear
      Different requirements for oil filters?

      By Grumpy Bear · Posted

      Do you know WHY the filter relief setting was increased to 22 psig?    When the new system goes into the second stage the pump volume ramps up considerably. It was found that the 15 psi filter bypass setting put the filter in bypass on a warm engine when the second stage was activated. Raising the filter bypass setting forced the filter to do what it designed to do. Filter. Preventing debris from circulating during high load, high rpm operation.    So next question is how did GM find this out? VLOM/lifter failures and a deep dive by Melling Corp.    Last question. Is it required? Look at it like this; a motor may be equipped with a rev limiter. But it only works if the set point in reached. That 22 psig setting only matters if the pressure differential across the filter media exceeds 15 psig during normal warm operation. Second stage kicks in around 3000-3500 rpm.    I can't answer your question because I don't know you and how you use the truck. But I think there is enough information here to let you decide for yourself. 😉
    • Coastie05
      give me some tips to make my truck look better

      By Coastie05 · Posted

      Go back to OEM wheels. 
    • newdude
      2020 Trailboss 6.2 replacement

      By newdude · Posted

      Probably not their first rodeo, so it should go as planned most likely.  Typically the service manager or tech doing the swap will put some seat time to shake it down after they get it all put back together.  We usually put 50-100mi before we hand them back so if something happens, its not after you get it.  A coolant leaks, oil leaks, a ground left off or loose, vibration, etc.     The new engines so far have been good?  There's been a couple that have popped out there again (the replacement engine) but most have been okay.  

  • GM-Trucks.com Clubs

  • Popular Contributors

×
×
  • Create New...