Chris Further to your very helpful response I contacted TomTom but they denied all knowledge about how they could cure the problem so I would appreciate any further information such as contact details etc at TomTom. The only suggestion from TomTom was for me to contact Jaguar to establish if there was a gap in the athermic windscreen through which the TomTom could receive the GPS signal. Jaguar were similarly unhelpful but explained that the reason the Jaguar built in SatNav did not have safety camera information was because it was illegal in certain countries where they market the XF. This obviously does not concern Mazda as my daughter's Mazda 6 bulit in SatNav(TomTom) does include safety cameras. They also suggested that the heated front windscreen could create a "Faraday Cage" which would prevent the GPS signal but again this problem does not occur on the Ford Mondeo heated front windscreen so I believe that was a bit of a red herring. I did ask Jaguar why they did not provide a socket so that the TomTom could receive the GPS signal viaa the "shark fin" which is the route for the GPS signal for the built in SatNav but got no response. Any further helpful input would be much appreciated
