You will need to scan the abs system to get an idea of what the issue is. These trucks have a common issue of the front wheel speed sensors going bad.Use this link to find a good shop near you.
https://repairpal.com/repair-shops
Alex
RepairPal Certified shops can diagnose and repair your 2003 Cadillac Escalade. They provide transparent pricing with a minimum 12-month or 12,000-mile warranty on repairs and services.