Service System Stability Escalade

[npower24]

Hello all,
I have a friend with two escalades that wants me to do some work.

FIRST CADILLAC ESCALADE 2002 SUV EXT:

The biggest issue on the first one a 2002 EXT is that service system stability light is on and the car randomely govenors down to an almost idle speed randomely when driving, then picks back up to the normal speed:

1.From what I have been researching that light on is ONLY driven by one of two things bad ABS sensors or BAD steering wheel position sensor? is this true? If so what about the brake pressure modulator, does this come into play?

2.Can I get these codes from the manual method through the DIC- the Info Up and On/Offswitch method or do i need to take it to the dealership (not autoparts store) and get them to find the service stability code?

3. How should I go about fixing this issue- replace ABS sensors first or replace steering wheel position sensor first? or do niether and get the codes first?

SECOND CADILLAC ESCALADE 2003 TRUCK:

4. Griding Noise when accelerating- I think this is the differential going bad, how do i tell if it is the differential or another suspension component vs transmission (i think transimissons only whine, they dont grind)?

5. Should I check all the fuild levels first in front and rear differntials, and transfer case first?

6. If it is the differential vs. something like the hub bearings how can I tell what the noise is? and if it is the differential is it worth the 1500 to rebuild? or should i just go on ebay and buy a remanufactured one and not mess with the inside of the distributor but just remove the old differntial and replace with the refurbished one?

7. Will the ECU throw codes showing differential or hub bearing issues (definably issue with other escalade 2003 EXT truck)?

Thanks for the help
-Nate
Mechanical Engineer
Orlando, FL
850-418-2355

 

[Stanley Mitchell]

From what I noticed with mine is that it will disable power to the transmission untill traction is regained around 10 to 20 seconds. I had to shift to netural then back to drive to re-engage the trans. This is a saftey feature that I was impressed with. I paid about 300 to have the dearler replace the part, but I'm quite sure you can get it fixed for less.
carobd2shop.com

 

[rockenthebowtie]

Probably the best advice would be with those type questions is not to do anything... all your going to end up doing is getting yourself in a bind by spending all this money on parts and still wont be fixed.... I'm not trying to be a smart a$$ or anything just that it seems that you have very little to no knowledge of where to start... I've seen long time friendships break up over stuff like this... hope everything turns out okay

 

[npower24]

Rocket that was the weakest excuse ever, but hey you got me to respond back! Yes so I will type this out so far, hopefully it helps someone else out. But from 2002 onwards all cadillacs/gmc/chevy non utility trucks have this new Vechile Speed Sensor system. The issue steams from not changing out your stock front and rear shocks and struts on the normal maintence schedules which after time leak air. The air compressor on the back of the vechile will try to pump them up and runs continually until it burns out. When the air compressor burnt out it fried out my wheel position sensor under the steering wheel and the master brake sensor in the engine compartment. I am going to switch to the Arnott Passive non electronic front and rear shocks. I am also going to replace/check the transmission, transfer case, differential front and rear liquids and grease the u-joints. The Arnott C2527 is for this 2002 Escalade EXT SUV contains a chip also that shutsoff the electronic VSS computer. which is great to avoid futuristic police from shutting down your car . Let GMC dealership get the codes for you for 120 bucks then replace the sensors from discount sources

 

[rockenthebowtie]

Well I'm sorry you feel that way.. only just so you know the front shocks are not air supplied its only the rear... the steering wheel rotational sensor and brake master cylinder pressure sensor are all on different circuits so theres no way they could of been affected by continuous running of the ALRC Compressor.. the 2 sensors provide input data to the EBCM thru a voltage signal to maintain better control and or stability under certain driving conditions, the ALRC Compressor is turned on or off by the ALRC Module that recieves ride hight input thru a voltage signal by the level sensors that are mounted on the body and frame of the vehicle to maintain proper ride hight when loaded down such as towing... when the ALRC Module determines that ride hight is out of the preset programmed value the ALRC Module will command the ALRC Compressor on or will command the exhuast valve to bleed air from the rear shocks until the preset value is met.. so again the ALRC Compressor had absolutely no affect to the 2 mentioned sensors... hope that helps