02 Tahoe ABS & Traction Assist Light ON

[kile44p]

Recently during a heavy rain storm, the "Traction Off" light came on above the Traction Assist Button for a couple of minutes. Few days later, now the ABS and Traction Off light is on all the time. Any ideas? Naturally this happens when the warranty has just run out and the manual only says to consult dealer.

Thanks in Advance

[kile44p]

Mechanic told me to check the speed sensors... I can trace the wiring, and see no defects. How do you clean the speed sensors?