Can anyone tell me how to enable the self diagnostic mode on an '03 Escalade?

The service ride control message came on and I want to know what the problem is before taking the truck to a dealer.

Ive read about how to enter diagnostic mode on older models, but my DIC has no on/off button nor up arrow.

Thanks

Mejia, I'm from mty mex, also. And had the same message reported from my esv. it happend hours before taking it for it's first service, so i had it checked for free. And they came out with nothing. After researching the problem in the web i found out that it is normal, unless they light stays on for more than one day, the ecm systems on our suv's have a lot of bugs, so a couple of those "sensor errors" are common. But i belive the escalades are afraid of mty's potholes :D.