Raymarine Raystar GPS Units Have A Battery
I have purchased at least three Raymarine Raystar GPS units because they just quit working. I sold my boat that had the unit and now I find out that there is a small 2032 battery in the GPS head. Here is a quote from someone who has actually replaced one of these batteries and saved having to buy a new $300.00 GPS unit.
Get a small phillips screwdriver and a multimeter if you have one. On the bottom of the unit there is a foam gasket. It has a fairly heavy plastic base on the foam. DO NOT PEEL AWAY JUST THE FOAM - peel away the foam ALONG WITH the heavy (clear) plastic. It should come off the GPS including the adhesive leaving the GPS not sticky.
There are 6 Phillips head screws holding the GPS together. Take out those screws and the GPS should come apart. The battery is in a slot on the board. You can check it with your multimeter. Mine was flat 0V. Replace with a new CR2032 positive side up as shown by the + sign on the battery slot.
Put back together carefully. Note, there is an o-ring that keeps the unit sealed. I had trouble with the o-ring slipping under the board. You don't want that. I had to put a tiny bit of teflon grease on the inside of the GPS cover where it contacts the o-ring to allow it to slip together easily. Make sure the board is all the way down and the o-ring is not trapped under the board at all, even a little will make it impossible to put back together correctly. Also note there are alignment marks on the top cover and the base - a small arrow on the base and a dot on the cover. This is so the LED lens lines up with the LED.
Hold everything together and put the 6 screws back in. The base should be flush inside the cover. If not, the o-ring is probably out of position. Take it apart and fix it.
Hope this helps someone save a few bucks.