ABS Light On, no apparent reason on 2001 Chevrolet S10

I have a 2001 Chevy S-10 Blazer ZR2. I replaced both front wheel bearings and have checked all the sensors from all 4 wheels. All seems secure and unbroken. I used a code scanner, scanned and received no codes. Cleared anyway, then the light when off for a second and reappeared. The only time the abs light went away was when I hit the control module with my fist and went for a test drive. The light reappeared the second I hit a bump. My conclusion is I have a bad abs module, but I have heard 2001 chevy s10's have had a nasty habit of having this abs problem. Anyone have any info on whether I am accurate or if I am missing something? I check all connection at the control unit as well.

Asked by for the 2001 Chevrolet S10
when the code re appears right away, this indicates some type of electrical failure. you need to check for ac voltage out of each sensor to verify that they are wroking. toner rings, sensor mounts, wiring all could be an issue. be carefull hitting control units, they are devices that need to be carefull with, not abused. take it to a shop that can verify the problem. the reason you may be showing any codes are that the codes may be stored in history area. do not erase the codes until you have it checked.