I have my Garmin 51 connected continuously to the power connector, and it comes on and off automatically with the ignition.
Last Wednesday I had an 80-mile trip then put the car away in the garage. When I brought it out this morning, the 51 displayed "Battery is low". As culzean says, doesn't say a lot for the battery that it goes flat in five days, WHEN NOT BEING USED.
If it's like all the other Garmin GPS's I've recently owned then you leaving it in standby is it being effectively being used. A similar analogy, you wouldn't expect your car battery to last very long if you turned off the engine, but left the ignition on.
Yes but it is not in standby, that is my grouch - I have always pressed the power button for a long time until a message 'turn off the device' with options 'cancel' and
'off' ( and pressed the off on the screen ) - which Garmin support assure me is the correct way to turn it of rather than just press the power button for a few seconds to put the unit into standby.. you can tell it is not in standby because unit will recover from standby state very quickly without having to reboot, mine always fully reboots when I turn it on - but the battery icon is red and the message 'low battery' normally comes on pretty soon.
All garmin support could come up with was that I was not turning the unit off properly - or not charging it properly, but I have been on trips of 5 hours or more with it plugged in and next day it still shows low battery, but garmin refused to accept this as a fault...
They also confirmed that the battery life is a measly 30 minutes ( but i thought that was the life if you left it fully powered up, seems i was wrong and that is actually the life of the battery when unit is fully turned off
).
I never leave garmin plugged into the car when not using it - it is turned off and put in its case.