Thanks for the reply, the tablet is mounted on the dash with a clear view of the sky, the tablet specs indicate that it can receive four kinds of satellite signals, when using GPS test it can be seeing 12 satellites (I've only ever seen GPS and GLONASS satellites) with 5 in use but still no fix. I have used Google maps, copilot and Waze, all fail in the same way. Sometimes after perhaps 45 minutes a fix is made and after that whatever map service I'm using seems to be accurate and remains working indefinitely, the problem I seem to be having is getting the first "fix".