Vehicle Speed Sensor.

Gday everyone. I have a 2002 RAV4 2.0 Manual. I’ve been having problems with my speedo dropping out and my engine light coming on, and yes 100% it’s the VSS. When this fault happens (speedo drops to 0) my lights start strobing to the revolution of my wheels ? So in other words the faster I go the fast my light switch from high to low beam. But once I disconnected the vss they stop strobing. Then some days when it’s connect the speedo is fine. Could it be moisture ? Bad earth ? Or just a buggered vss ?
Any help would be great guys. Been stuck on this issue for a while.