I assume you mean the oil light? I've been told it's flashing because it takes a reading from the rev counter & as the rev counter isn't working it's not getting a reading hence why its flashing mate which makes sense as it started flashing the same time the rev counter stopped working (a few months ago).

The oils fine & the pressures been checked & thats fine too.

The cars been in daily use on the motorway & it's been fine