BRAKE SYSTEM on 2004 GMC Yukon

MY BRAKE LIGHT IS ON MESSAGE ,CHECK BRAKE SYSTEM. THIS IS AFTER 30 DAYS THE BRAKE CYINDER HAS BEEN REPLACED. WHAT CAN BE THE PROBLEM?

Asked by for the 2004 GMC Yukon
1 answer
Take it back to the shop who did the work ASAP, something is VERY WRONG and brakes are a SAFETY issue, so don't mess around with this!