Missing centre cap / ABS ligth on - Audi TT Roadster 2000

[Toddly 10]

Missing centre cap / ABS ligth on - Audi TT Roadster 2000

Yesterday morning I found the right back centre wheel cap had fallen off (found on pavement). I drove to work, no problems. Lots of rain during the day.

Today, as I drove to work, the ABS light came on and has remained on since.

Is this related and a minor problem with a sensor, or is it likely to be unrelated?

How much would it cost to fix?

Any ideas? Thought I'd check here before I venture to the local rip off car mechanics...

Thank you

[Scotty 1,335]

I can only think that perhaps the wheel took a knock which caused the cap to come off and the ABS sensor to fail?

Total guess.