Service Brake Booster Message

[Joe Marcinski]

Hi,

Just joined and would really appreciate some help with an incredibly annoying "Service Brake Booster" message that pops up every time the truck is started. It is on its second new master cylinder/brake booster unit, multiple bleedings of the brakes, dash cluster has been completely rebuilt. Brakes work just fine and always have.

I did the search and with all due respect the answer there does not really help.

Has anyone had this problem and actually been able to diagnose and correct it?

Thanks very much,

Joe M.

 

[07burb]

Joe, what year is your Tahoe? I've moved your thread to a more appropriate section so that it doesn't get lost in the Intro section :handshake:

 

[Joe Marcinski]

Thanks Burb,

It is a 2003 Tahoe.

Joe M.

 

[07burb]

Other than the message does everything seem to work like it should when braking? Does the message ever go away or does it come on and stay on?

 

[Joe Marcinski]

Hi Burb,

The message comes on shortly after the truck is started. I can make it go out by hitting the message button on the steering wheel. The message generally doesn't return until the next time the truck is started. The brakes work fine. The vacuum booster has been replaced twice and the master cylinder has been replaced once. I have searched for vacuum leaks, but have not discovered any. The instrument panel has just been reinstalled after a complete rebuild. There was some corrosion on the connector surfaces of the cluster and the hope was that the "black death" was possibly causing a false signal to light that warning.

The steel lines have been replaced (due to a corrosion induced failure). Braided Teflon/Stainless lines have been installed at all flex line points. The brakes have been bled at least 8 times. The calipers have been rebuilt.

The truck works great (although I wouldn't mind another 80 to 100 HP), but this continuous message has just about got me to the point of looking at buying another truck. I don't like things that don't work and I really don't like things that work just fine, but tell me otherwise. It is very frustrating. I have been preparing and racing small formula cars for almost 40 years and I am told that I am a pretty good mechanic. I do not claim to understand electronics and there are things that I simply don't bother with and take them to a shop that is (at least in my eyes) very, very competent. This silly thing is really getting annoying. Sorry for the little rant!

Joe M.

 

[07burb]

I can definitely see how that'd be annoying for sure! I get annoyed by the same types of things

1. Let's keep the message in perspective. The Tahoe runs fine and brakes fine and it appears you've taken the proper measures to make sure everything is in good working condition. So we know the vehicle is not a danger to drive.

2. I wonder if the message is something that needs to be reset so that the system knows that it's been serviced. You know, kind of like the oil change light you have to reset that so that the system knows you changed the oil. I'm not sure if this is the case or not but a shot in the dark.

Those are my thoughts. If you like the Tahoe I'd keep going with it. It sounds like it's in good condition with an annoying message which doesn't seem to mean much at this point. As a last ditch effort you might take it up to the shop you trust and tell them what you've done thus far and what the message says. They may have seen that before and know the fix pretty quickly.

 

[Joe Marcinski]

Hi Burb,

Thanks for taking some time to consider this. We (the shop I use) have plugged in to clear the code several times after we have worked on it. I have pulled off the various connectors at the sensor points and cleaned them thoroughly, disconnected the battery for an hour or so and then turned it back on again. The message sometimes doesn't appear for 30 minutes or so, but it always does seem to return.

I have often wondered if it might have something to do with the plastic intake manifold. I have checked for vacuum leaks around the tube coming out of the intake, but haven't found anything. I am really not up for replacing the intake at this point, so I guess I will take your advice and blow it off as a "ghost in the machine".

It does however make a used State Highway Patrol Tahoe PPV start looking like a good option. At least I would get the extra HP I would like!

Thanks again,

Joe M.

 

[07burb]

:hmm: that is rather perplexing :think: It makes me wonder if there is some other minor issue somewhere else that may or may not be directly related to the braking system but for some reason makes the system throw this message. The reason that thought is crossing my mind is because I know in my 07 every little thing that goes wrong seems to throw the Stabilitrak message on my DIC when the issue very rarely has anything to do with the Stabilitrak system. It's an extremely annoying thing and I have no idea why GM programmed it that way :shrug: Obviously, that doesn't help you at all in your troubleshooting of this message but that seems like a decent possibility of what is happening. I wouldn't have the foggiest idea of where to tell you start looking for this needle in a haystack :facepalm: