light came on today, scanned it with my obdII scanner and no codes. what next, checked the connections to the wheel sensors all seem ok, anyway to reset the light? 2000 S70 glt se.

 

test drove it today and the light went off, so??

 

A generic scanner can't read ABS codes. Probably needs a module.

 

First time post but I have an S70 and have same issue but the reason it goes off is that when you first start the car, it self tests and when you reach 15-20mph it will usually go off and then stay off until it plays up again.

These units will fail and you can try repairing the unit, you can try cleaning the sensor and you can also check the condition of the ABS rings (to see if they are cracked) but it will get worse!

 

^That. Possibly a wheel speed sensor, as well.

 

I used this gentleman for a replacement module and have been more than pleased: https://www.midwest-abs.com/