Abs/Trac light on dash flash off and on. on 1999 Toyota Avalon

This has been going on for 3 weeks now.Some days the lights go off for a day and then right back on.The lights 90% of the time are flashing.Two auto shops have checked for codes but nothing shows up?I am considering removing the sensors one at a time and will try and clean them.

2 answers
wheel sensors
When the ABS indicator light on your dashboard comes on, it usually means that your ABS system isn't working properly and needs to be checked. However, your normal, non-ABS braking system should still be functioning.