A3 '06 ABS & traction control warning light randomly come on

Both ABS & traction control warning light randomly come on and also sometimes go off. Pressing the ESP button does nothing, but switching engine off sometimes resets both. In this case, with no lights on, pressing the ESP button works (ie it illuminates the anti skid light), and turns off properly too, so it appears whatever's causing them 'both' to illuminate locks out the use of the ESP button.

Any pointers??

Thanks

Have you hooked it up to a scan tool to see if you have any pending trouble codes that haven't set the check engine light or hooking one up when the lights are on. Off the top of my head I would take the educated guess that you have a wheel speed sensor going bad or a connection to a wheel speed sensor is corroded. Best bet is to hook it to a good scan tool like a tech II. Let us know what you find. It helps with diagnosis of others with similar problem.