Hello. I have a 2003 1/2 Ton Suburban 5.3L Flex 4WD with 142,000 miles. I have an issue with the ABS light coming on when driving slow and hitting speed humps. An audible tone is heard (like the one that tells you a door is not closed (ding, ding, ding)) and the ABS light comes on. Typically when I turn off the vehicle and then re-start it the ABS light goes off but this is not always the case. It will also come on intermittently without the tones when first starting out but will shut off after moving a bit. So far, I have checked the engine-to-chassis ground straps (cleaned and re-seated), removed the front wheel ABS sensor cables, then cleaned and re-seated them along with the tone ring (after testing the resistance as outlined in the Chilton's manual - appeared normal), inspected the cables for wear and visually looked at the ABS module located under the drivers door for any obvious loose connections etc. I am thinking this is a grounding issue of some sort but would like some suggestions on how to better troubleshoot this. I am hoping it is not a problem with the ABS module. Any help would be appreciated. - Thanks!