LS4 Performance - Having some issues with the GXP

Like the title says I'm having some issues with the GXP. For the past couple days my DIC has been flashing service vehicle soon, service ABS, service brake system, TC system off, stability system off, and the steering assist off. I think thats all of them. lol. I've scanned it and there's no engine or ABS codes in the car, and all the fuses are good. it has to be something easy, just not sure where to go next. Could there be a wheel bearing going out, or maybe a broken wire down by the wheel. Any help would be great, Thanks

All of those systems read vacuum. Could be a leaking or broken vacuum line. Check them.

Check the wiring from the ABS sensor connector to the hub itself. If they rub the axle it can wear down to the insulation and cause a short. If you see no wiring fault it is likely to be the hub but you need to have a shop pull the ABS code for you. They should be able to view the history stored code.

Normal trouble code scanners will not pull the ABS codes from these IIRC....I had to use Snap on MODUS to read my ABS codes on my 2005.

All of those systems read vacuum. Could be a leaking or broken vacuum line. Check them.

Do what?

Like the title says I'm having some issues with the GXP. For the past couple days my DIC has been flashing service vehicle soon, service ABS, service brake system, TC system off, stability system off, and the steering assist off. I think thats all of them. lol. I've scanned it and there's no engine or ABS codes in the car, and all the fuses are good. it has to be something easy, just not sure where to go next. Could there be a wheel bearing going out, or maybe a broken wire down by the wheel. Any help would be great, Thanks

I think you're on the right track. The items you list are the most common causes for the messages you're seeing.

While the previous poster has a point regarding vacuum, any leak bad enough to fire those messages i8n the DIC would also manifest themselves as drivability issues and would also set a PCM code that you would have seen when you scanned it.

I'd look at the hubs and see if it's a wheel bearing or sensor wire problem.

The only other common thing that causes is this a K&N filter that's been freshly re-charged with a bit too much oil. It blows off the filter and into the MAF, which causes those messages to appear, despite no PCM codes.

Check the wiring from the ABS sensor connector to the hub itself. If they rub the axle it can wear down to the insulation and cause a short. If you see no wiring fault it is likely to be the hub but you need to have a shop pull the ABS code for you. They should be able to view the history stored code.

Normal trouble code scanners will not pull the ABS codes from these IIRC....I had to use Snap on MODUS to read my ABS codes on my 2005.

I'll put it in the air and do some checking at the sensors. I had my buddy use his snap-on scanner, but there where no codes stored.

Does the Abs system really take MAP readings into consideration? I could see the traction control and stability control so it can provide torque management....

Check and see if you have brake lights. If the brake position switch goes will get some similar warnings in the Dic. Also that is all controled by the bcm. Might need to run a diag of that computer

If you pull the vacuum line of your break booster you can get a generic abs code. But simply because some part of the brake system ie the booster is malfunctioning.

Like the title says I'm having some issues with the GXP. For the past couple days my DIC has been flashing service vehicle soon, service ABS, service brake system, TC system off, stability system off, and the steering assist off. I think thats all of them. lol. I've scanned it and there's no engine or ABS codes in the car, and all the fuses are good. it has to be something easy, just not sure where to go next. Could there be a wheel bearing going out, or maybe a broken wire down by the wheel. Any help would be great, Thanks


do you have C.A.I system installed or any other aftermarket cold air intake system other than factory?

if yes than i might have an answer for you.

do you have C.A.I system installed or any other aftermarket cold air intake system other than factory?

if yes than i might have an answer for you.

Nope it just has a factory box, with paper filter.

Think I finally got it narrowed down to the cause. It appears to be my ABS module, its getting the right volts going in but its only putting out like .9 volts. Is this common, if not that would explain why one is expensive.

i have very simialar problmes, how did you test output voltage of the module itself?, i am getting code u 103 when reading abs

I also have this same problem the codes r b0550 b0898 b0896 i believe its abs control module a wire becomes weak and sauter breaks the connection

My car shuts off everything too every now and then. I scanned my bcm with a tech2 and came up with two codes that were irrelevant. There is a tsb on this matter, and pontiac said to reset the tire pressure monitor in the dic (information button) I reset everything and no dice. If you have a bad sensor then the bcm will tell the tech2 which one it is. If it can't figure out which sensor it is, then the bcm will throw a seperate code. In this case, the abs module will need inspected, and all related wiring. (especially grounds) the steering wheel position sensor can also be to blame.
My car acts up when cold and is fine when hot. Something is expanding and creating continuity.
I have had this car up on the rack and inspected everything related.
I have used scanners, and am still stumped. I am in school for this shit, and nobody has answers other then "just strat replacing stuff"

has anyone figured out the u codes for abs? and can anyone get a diagram of the abs module? or where it leads to bcm?

im going to check the volts of the abs parts this sunday and will let you know what i have noticed. i have all lights break tc abs stability control service effort steering. someone said it can be a tpms. idk but this is pissing me off so much about to trade car in. just pisses me off decides to go on right before i put new rotors and pads on car