This is what I emailed Garmin from their website on May 25:
Message Body:
The images of the 540 on the webpage shows depth contours. I cannot get these to display on my 540. Also when I try to have the unit "guide to" a waypoint I get the message "Auto Guidance unable to calculate route. Starting Position not within safe depth" I can be in 10' or 50' of water. The website is extremely misleading. Will a 540 chart a course? or display the contours?
They replied on June 1:
Thank you for contacting Garmin International. I would be more than happy to help you with this today. The GPSMAP 540 will be able to display the spot sounding for the chart coverage that is preloaded in the unit. It will require you to be zoomed in close enough to the area in question. As well you want to make sure that you have your sport sounding turned on as well. This can be confirmed by doing the following steps.
1. From Charts choose the Navigation Chart, and then press your menu button.
2. Scroll down to chart setup and press select.
3. Then highlight the appearance option and press select again.
4. Make sure you have spot sounding turned on and that you have detail set to the most so that you are getting the best out of your chart.
I would also confirm that you are running the latest software version as well. This can be done by choosing configure from the home screen. Then select system and choose system information. This will allow you to see the software version on the unit. I would recommend updating to 4.40 if not already on this version.
In order to update the software you will need to have the link that is pasted below and a blank micro SD card that is 2 GB or smaller in order to unzip the file to card.
http://www8.garmin.com/support/collecti ... 0-00614-00
The BlueChart g2 vision cards has a new auto guidance feature. This mapping software along with a compatible GPS device has the ability to create a safe route for the user avoiding known hazards and obstacles which are loaded into the mapping software. It also takes into consideration the "Safe Depth" and the "Safe Height" settings for the vessel, which the user has set up in the device, when calculating the route. One safety feature built into the software is it will not calculate a route through any area where the spot sounding depths are less than 6 feet with older cards dated before 07/2007 and less then 3 ft after card dated 7/2007 to present. Your start and ending points must be in an area that is 3 ft map depth or higher and be able to safely navigate you to your destination in order for the auto guidance to work. This is to prevent a route from being generated which has the possibility to cause the vessel to run aground. This is a safety feature which cannot be overridden when using the auto guidance feature. Even if the user has set their "Safe Depth" to less than 6 feet (e.g. 2 or 3 feet), the auto guidance will still not calculate a route through waters under 6 feet of depth.
With Best Regards,
Michael B
Product Support Specialist
Marine Team
Garmin International
My unit would not show depth contours regardless of what Garmin says until I purchased the g2 vision chip. Their website is very misleading, the base unit just will not do this. In addition it will not chart a course to any destination unless you purchase the g2 vision.