Anybody replaced a speedo/ABS sensor before?

'14 Multistrada 1200GS. First ride in a few months, and:

  • speedo reads 0 all the time
  • odometer not increasing (wooo!)
  • ABS warning

I’m pretty sure all signs point to speedometer / ABS sensor. I’m also pretty sure that ABS relies on both front and rear wheel sensors so that isn’t a clue as to which might be bad - but does anyone know if the speedometer gets its signal from just the front (if so that’s likely the bad one).

Anyone here replaced one of those before?