Yesterday my Sat Nav TMC reported that the M6 was closed between junctions 2 and4 because of roadworks and recommended a diversion. There had been nothing on the radio nor on any matrix signs on the M1. I know that there had been road works there for a long time but that they were finished so I decided to ignore it. Sure enough the M6 was completely clear and even though I turned TMC off for a while, the warning came back. The sat Nav system itself was working perfectly apart from this wrong warning.