VSC TRAC, VSC OFF, ABS LIGHTS HAVE BEEN COMING ON AND OFF SINCE I PURCHASED THE VEHICLE NEW IN 2004. DEALER COULD NOT FIND ANY PROBLEMS OVER THE YEARS. LAST WEEK LIGHTS CAME ON AND STAYED ON FULL TIME. ABS SYSTEM SEVERELY SHOOK WHEN BRAKES WERE DEPRESSED. DEALERSHIP REPLACED MASTER CYLINDER AND BRAKE BOOSTER SYSTEM. COST WAS $1,200. WARNING LIGHTS STILL WERE PRESENT, AND THEY WERE RELUCTANT TO LET ME LEAVE THE DEALERSHIP WITH THE PROBLEM STILL PRESENT. THEY DECIDED THAT THE BOOSTER WAS AN "AFTER-MARKET" PRODUCT AND NOT PROPERLY COMMUNICATING WITH THE COMPUTER. DEALERSHIP WANTS ANOTHER $600 TO SWAP THE BRAKE BOOSTER, BUT STILL NO ASSURANCES THAT THE WARNING LIGHTS WILL NOT COME BACK ON. THIS HAS BEEN PROBLEMATIC SINCE THE DAY I PURCHASED THE VEHICLE. IT APPEARS THAT THIS IS NOT AN ISOLATED ISSUE WITH THE SEQUOIAS AND TUNDRAS. *TR