DIC displays "Service Brake Booster"

Good afternoon everyone,

First off, I've done lots of research on this issue and still don't have it solved so I figured it was time to write a post to see if I could get closer to a solution.

I test drove my 2004 Avalanche and everything was fine; no messages or lights on. I decided to purchase the truck from the private owner and he delivered it to me. My wife made the actual purchase as I wasn't home at the time. I got the truck registered and went to drive it and noticed the "Service Brake Booster" message on the dash. It won't go away and none of the steering wheel buttons do anything other than the ones for volume and changing the radio. But, when I test drove the truck, the buttons for sure worked. So, currently I cannot see the odometer reading because the buttons aren't working and the "Service Brake Booster" message won't go away.

I read that having the wrong size alternator could cause this issue, I know this is not the case because I looked up which alternator should be installed in my truck and verified the model of the one that is installed.

Some people say to check the brake fluid, but I believe that is for a "Service Brake System" message and not "Service Brake Booster", but my fluid level is at the max fill line like it should be.

Another thing I read is that if the seller had swapped clusters without reprogramming the "new" one, it could show this message. The truck has a hydroboost setup (which I velieve came with most models of Avalanche) and not a brake booster. I'm not sure if the "Service Brake Booster" message is specific to having a brake booster over a hydroboost or not?

I've called multiple dealers, and none of them seem to have ever heard about this issue. And they want to charge me $100 to diagnose and $85 to reprogram. But I would hate to take it to the dealer and they reprogram it, and it doesn't fix the problem. I always work on my own vehicles; the only thing I don't do is mount/balance tires and alignments because I don't have the machines to do so. I hate giving my vehicle to someone else to work on because you never know if it's done right, so you can see why I may have hesitation to take it to a dealer.

Anyways, I'm not finding much information out there about reprogramming it myself, so I may have to just bite the bullet and take it in to have them do so. But I wanted to see if anyone else out there had a similar issue that they resolved. Any information would be helpful at this point.

Thank you!

I have a bluetooth OBDII plug that I use in conjunction with the "Torque" app on my phone, but that just reads and clears "check engine" light codes. Do other apps allow you to get more information about the DIC display?

I started reading into the TEC2 scanners but they seem pretty pricey. I would have to read more about them before I would decide to buy one.

You mentioned:

JVZL1 said:

[shadow=red,left] Get a reader or there are APS if you like doing your own. It saves money and headaches.

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Is this reader that you talk about the TEC2 scanner? What APS are you talking about? I'm all about saving money and am a big DIYer.

As far as unplugging the battery. Are you saying I should unplug the battery to see if I can use the buttons again? And I've tested all of the fuses with a multimeter: none were bad.

Thanks for the quick reply!

Gotcha. I feel like I disconnected my battery once before and the message went away for a little bit, but the buttons still didn't work. I'll have to give that another try and see what happens.

JVZL1 said:

I've checked into theTEC2 scanners and there is a lot of read about Chinese clones that are junk. There are members on here may chime in.

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I have a Chinese Tech 2 clone. Great piece of kit, love it, better than my OTC4000E or AutoEnginuity for working on any GM up to about 2013. It is by far and away the best diagnostic tool for these vehicles. I did upgrade my on-board power supply board to the original Mornsun chip.

BUT there are several different manufacturers of these out there, the vendors come and go with rapidity and so things are a bit of a crap shoot whether you will get a good one or a bad one. If you buy one, make sure you purchase through eBay or AliExpress so you have purchase protection in case yours is junk out of the box.

Second thing to know is while the Tech 2 is a powerful tool on it's own, teaming it up with TIS software on a computer adds another dimension for downloading, printing, graphing and programming. HOWEVER you need a computer with a physical parallel port to use that software.

Prior to 2005, GM supplied programming updates via CD. Those are readily available. Post 2005, GM switched to an on-line subscription system. It's primarily aimed at dealers and shops, but shadetree mechanics with a clone Tech 2 CAN purchase a 3 day subscription for something like $50. And you CAN search GM's database for your serial number first to see if there are any programming updates for your specific vehicle.

And that's the downside. TIS is not like a program such as TunerCats. You cannot build a custom program for your PCM or other modules. GM will update things as they see fit and it's very vehicle-specific. EG: let's say that GM had a lot of complaints about, oh, a harsh 1-2 shift on units with the z71 RPO code. They might come up with a software fix by changing the pressures or shift points or something, but that will only be available to serial numbers that left the factory with z71 components installed. If you add an option later, the system won't let you download the required programming. A GM dealer can call in and GM will make a new custom firmware for your truck, but as far as I know, this is not available to the great unwashed public.

Now, if you replace an existing module with the same type of unit, you can generally use the Tech 2 to marry it to your vehicle. So for example, if your security module crapped out and you bought one from the wrecker, you will probably be able to make it work with your PCM (but check the FSM first, there are some modules that just can't be re-married ever again, depending on year and vehicle).

There are ABS Codes which some readers can read and clear:

https://www.innova.com/en-US/Product/List/87448f82-f9a3-4c87-9384-4c0dea8a7168?r=0.42042755400502174

buickwagon, I appreciate the info on the TEC2 scanners. I'll have to do some more research and see if it's something that will actually be worth it for me.

ygmn, I actually drove out to my buddies house last night. He has one of these ABS scanners. Looks like I have all sorts of codes being thrown (most relate to the wheel speed sensors), but when we cleared the codes the "Service Brake Booster" message didn't go away.

I'm going to fix a few things just to get these errors to go away and then continue on the search.

Thanks for all your input! Keep it coming if anyone else has seen this "Service Brake Booster" message before.

Thanks again!

Will do. I'm going to order the parts I need to fix all of the ABS codes but I doubt that will change anything. Either way those should be fixed.

What does owners manual say that error message means?

I have a 2002 so mine does not have that error

That, is a very good question...

"If a problem is detected, a warning message will appear on the display. Pressing any of the four buttons will acknowledge (clear) most current warnings or service messages. Some warnings that cannot be acknowledged (cleared) are: ENGINE OVERHEATED, OIL PRESSURE LOW, REDUCED ENGINE POWER, TRANS HOT IDLE ENGINE, STABILITY SYS ACTIVE, TRACTION SYS LIMITED and TRACTION ACTIVE. These warnings must be dealt with immediately and therefore cannot be cleared until the problem has been corrected."

"Service Brake Booster" is not in the list of codes that cannot be cleared; yet I cannot clear the "Service Brake Booster" code 

My "Service Brake Booster" message also doesn't show up in the "DIC Warnings and Messages" section of the manual  "Service Brake System" is in the manual but just basically says to service the brakes (nothing particular).

I will keep researching along and will update my progress. Hopefully someone else will come along that has/had the same issue.

theRog05 said:

I've called multiple dealers, and none of them seem to have ever heard about this issue. And they want to charge me $100 to diagnose and $85 to reprogram.

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Then they didn't look at their own service information:

SERVICE BRAKE BOOSTER

The SERVICE BRAKE BOOSTER message will be displayed when the supplemental brake assist signal circuit is toggled at 1.0 Hz with a 50 percent duty cycle. This message is also displayed if the instrument panel cluster (IPC) does not see an alive and well signal at key on. When this message is displayed it indicates a problem with the SBA and should be serviced or replaced.

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So the SBA or Supplemental Brake Assist is a canister looking thing that is mounted to the brake booster and I believe it isn't used for a hydroboost setup: please correct me if I'm wrong.

I removed the DIC fuse tonight and put it back in. The "Service Brake Booster" message went away and the odometer reading showed, but the buttons still don't work to change the value. The "Service Brake Booster" message will come back again after 5 cycles of turning the truck on and off again.

I've continued my research and some people say the clockspring could be why the buttons don't work, but I'm thinking it's related to the cluster in some way. I read another post on a forum tonight where a guy replaced the clockspring and it still didn't fix his issue with the buttons not working and had to have the cluster reprogrammed.

I wish I could just reprogram the damn thing myself but I don't have the tools to do so. What a headache this has been. 

This post makes me think that I need to find a TechII or head on over to the dealer...

https://www.justanswer.com/chevy/2yob6-speedo-fixed-display-reads-service-brake-booster.html

Ok, interesting bulletin. If I understand what it is saying correctly, if your truck has hydraboost but your cluster has been replaced with one that is programmed for vacuum brakes with a Supplemental Brake Assist (an auxiliary vacuum pump), then the message will be displayed because the cluster can't talk to the non-existent system. And no 2004 units came with vacuum brakes, according to that bulletin.

Just in case the bulletin is wrong or your truck is not really an 04: have you physically verified that your truck does not have a vacuum booster? Hydraboost has the master cylinder mounted directly to the firewall with hoses running to the power steering pump, vacuum boost has a large round metal can between the master cylinder and firewall with a vacuum tube running to the manifold.

So let's assume that your truck is an 04 with hydraboost. Perhaps the cluster was replaced one from another vehicle. If the other vehicle did not have steering wheel buttons, perhaps it is also possible that the cluster won't look for and talk to yours?

Next question: since the message will re-appear every 5 ignition cycles, it seems likely that the previous owner was well aware of the error. That implies that he was resetting it before every test drive. Given that he was dishonest enough to do that, what else was he hiding? Was the cluster replaced to conceal high mileage? You say he delivered the vehicle -- is this guy a "curbsider"? Did you ever meet him inside a residence or just at a convenient, say, coffee shop?

Regardless, the bulletin suggests that the dash can be reprogrammed via SPS -- that's the Tech2/TIS2000 programming combination I mentioned earlier. You connect the Tech2, read the installed programming version number, take it to the computer running TIS2000 (an old XP machine with real serial and parallel ports), enter the truck's serial number and check for the latest version for your specific truck with your specific options. Load that in the Tech2 and take it back to the vehicle to program it.

If you are anywhere near Muskoka Ontario I could help. Send a PM. Otherwise, yeah, buy your own or see a dealer. But not the dealer that never heard of this problem before!

I wonder if he installed new clister with less actual miles the the truck should have and it was set up for brake booster you do not have.

Have VIN run at dealerto see how this truck was set up from factory.

buickwagon,
My truck is truly a 2004 and I am familiar with the difference between a hydroboost and vacuum booster. My truck for sure has a hydroboost; like you said, in 04 they all came with a hydroboost.

It's possible that the cluster had been replaced and this is why I'm getting the message and the buttons don't work. But when I test drove the truck, the buttons did work. So why would he pull a working cluster and put in a non working cluster? The odometer on my truck now is displaying 117k miles which is about right from when I test drove it. So, it's possible that he switched clusters, but why would he put a non working cluster in if the miles were about the same? The only reason I could think of is if he had another truck with the wrong cluster and the one in my truck was the one he needed. I don't know, it all seems kinda screwy to me.

As far as the 5 ignition cycles, I was wrong: it must be inconsistent. Last night after I pulled the fuse I started the truck twice. Then today I drove to work (just under 10 miles) and right before I pulled in, the dreaded "Service Brake Booster" message showed again. But either way, I'm sure the previous owner was aware of this problem. The only thing that still gets me is that the buttons worked when I test drove it, and now they don't. So either he swapped clusters or this is just a huge coincidence where everything broke right when he delivered the truck 

I met the guy at his house to test drive the truck but only drove around for 5 or so miles. I'm assuming he at least knew who lived at the house because he went in it before we left for the test drive.

It looks like I'll have to ask around to see if anyone has a Tech2 to help me out or take it to the dealer to have them SPS program the cluster/IPC. I live down in Rochester, NY, about 300 miles away from you. I appreciate the offer to help, but it might be worth the $100 at the dealer instead of spending 3 times that to drive up to you and back. I'll be calling another few dealers to see if they know what SPS programming with a Tech2 even is.

That't not a bad idea 

theRog05 said:

My truck is truly a 2004 and I am familiar with the difference between a hydroboost and vacuum booster. My truck for sure has a hydroboost; like you said, in 04 they all came with a hydroboost.

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Ok, I's dotted and T's crossed then. Different people have different levels of experience, hard to tell over the internet sometimes.

I live down in Rochester, NY, about 300 miles away from you. I appreciate the offer to help, but it might be worth the $100 at the dealer instead of spending 3 times that to drive up to you and back. I'll be calling another few dealers to see if they know what SPS programming with a Tech2 even is.

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Yeah, if you are going to spend $300 on this, it might be better spent on your own Tech2 rather than a trip to Canada. In winter.

Good luck. Let us know how it all plays out. I'm really curious now.  

buickwagon said:

Different people have different levels of experience

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Totally understand! Especially since I'm new to the forum. But as for any forum, before I post something I try to do my research so I don't look like a complete moron.

buickwagon said:

Let us know how it all plays out.

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Will do! I just bought an O2 sensor, MAF Sensor and Wheel Bearing Hubs that I need to replace as soon as it's not that cold outside. This way I can at least not have awful gas mileage and also get my inspection done. I'll continue to ask around for a Tech2 and be sure to post any progress I have on this issue.

Next project for vehicles is replacing the caliper on my WRX. Once the snow melts off my roof I'll be able to install my new wood stove insert too. Always too damn much to do and not enough time to do it!

theRog05 said:

Will do! I just bought an O2 sensor, MAF Sensor and Wheel Bearing Hubs that I need to replace as soon as it's not that cold outside.
Next project for vehicles is replacing the caliper on my WRX. Once the snow melts off my roof I'll be able to install my new wood stove insert too. Always too damn much to do and not enough time to do it!

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So we have to wait until the end of July.  

Ha! I plan to get a few things done with the truck in the next week or so. Hopefully it's not THAT long!