I have a Navman 5600 installed on my boat, It was working as expected, but now there is ni gps signal. It did come on intimitly for a while. I have read the manual. and checked the settings. It seems to me that either the aerial is faulty or the unit may have a dry joint.. Should I take the main display unit to one of your dealers and have them chck it out????? Regards David D.leitch@optusnet,com.au