I believe you may have opened a new question - instead of replying back here - on this page.
If the fuse was TESTED and the tip of the vehicle adapter is a "good fit" when connected (is making contact) to the power socket, but the power indicator light does NOT come on, then the adapter may have failed - and will need to be replaced.
Now if this system is still covered by warranty (typically for a 1 year period), then that replacement should be done at no cost to you. If out of warranty, a replacement can still be purchased - either through Garmin support or perhaps through a local GPS dealer.
NOTE: IF this is a vehicle adapter that includes a "Traffic Receiver" AND you use that traffic feature, make sure you get the same (or compatible) adapter. The Part Number of that adapter is usually printed on a label located somewhere along the lead. Or the Garmin Customer Support folks can look up the proper part number for you - if you contact them.
In any case, you will want to get in contact with Garmin Technical support, and have the Serial Number of your dezl 760LM available so that you can get the correct part number and part for your device. I have the main support contact information below.
Australia Customer Support: 1800 235 822
Australia Fax Number: 02 8882 6150
New Zealand Customer Support: 0800 427 652
New Zealand Fax Number: 0800 427 646
I hope this information reaches you and helps.
Please let me know what you find or if you have any more questions.
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