Will the unlock codes not work if included?
That's right. When unlocked, the charts are encoded with a number recorded in the firmware of your specific GPS. You have to have the individual GPS unit that the charts were unlocked for.
The system actually works quite well aside from the wallet pain. An unlocked region costs less than what paper charts would cost for the same area and is comparable to chart books so it isn't unreasonable.
What is unreasonable is this:
I was putting new batteries in my GPS about four hours before leaving for a cruise and the battery connector spring broke off rendering the GPS unusable. I ran out and bought another GPS of the same model (GPSmap 76Cx) and contacted Garmin technical support to get new unlock codes so I could load charts in it. The rep said that he couldn't send me new codes until I returned the old GPS so they could be sure I wasn't selling it on Ebay with the charts unlocked.
I don't usually swear at tech support people but this was an exception and the air was blue. I pointed out that I had just bought, and registered on their web site, the exact same model so, what was I gaining? I asked, what happens if I'm in the middle of a cruise, my GPS fails, and have to buy another one? Do I stay there for 10 days waiting for UPS and Garmin to do their thing? Are you suggesting I just put off my departure or go without GPS on the off chance that I'm pirating your charts?
I finally took a digital picture of the GPS with the serial number visible and clearly showing the broken connector spring and emailed it to the rep. New unlock codes for all the charts I had purchased came back by email within minutes.
All this took a couple of hours when I was pretty rushed trying to get the boat ready. Imagine going through this someplace without cell phone service or Internet standing in a phone booth in the hot sun with a pile of quarters. Since you can only have two GPS units active, even having a spare on board wouldn't spare you this unless you had purchased separate unlock codes for it at the full price.
After this experience, I figured out how to stick a piece of metal in my broken GPS to make it work. I wouldn't depend on it for primary navigation but it sits in a locker with all the unlocked charts loaded it in. Because it has been de-registered from the Garmin system, I can no longer load additional or updated charts to it. However, I was able to copy the single file that contains the charts from the chip and save it on the laptop I carry. I have verified that I can reload this file to another Mini SD card and the charts will work in the GPS. However, if I stick this card in my other unit, it will not read the charts. Like I said, they have this locked down solid. I'm probably in technical violation of their terms of use but this GPS would only be used in emergency if my two registered units died so it comes under the fair use provision that lets you keep a back up copy of computer software.
Later: I see from Maine Sail's posts below that this information is somewhat out of date. Evidently, the preloaded Micro SD cards you get from Garmin are not unit specific and prices have come down considerably. That's good news because I like my Garmin set up except for the cost of the charts.
