Microwave stopped working, and its not very old. I wanted to know if it was the fues? How to replace it. 2008 i think LMV1680st

First of all, here is the main ONLINE SUPPORT page for your model:

http://www.lg.com/us/appliances/microwave-ovens/LG-over-the-range-microwave-LMV1680ST.jsp


You can download the owner's manual from the support site if you want, just look under the SUPPORT tab.

And here is a direct link to the Online Parts List and Service diagrams for that model:

http://www.appliancepartspros.com/partsearch/model.aspx?model_id=5520022


To view the Support Page or the service diagrams just use your mouse to click on the link, which is the underlined and highlighted text just above. This will open a new web browser page automatically for you and allow you to view the information at the website indicated and the contents of the Owner's Manual.

You may need ADOBE READER installed on your computer to read PDF documents like the owner's manual.
You can download this free at WWW.ADOBE.COM if necessary.
Click on the DOWNLOAD ADOBE READER button on right side of the ADOBE home page when you get there, the follow the onscreen instructions to install the software on your computer.

I will assume you have checked the house's main circuit panel for any tripped brealers and tested the electrical wall outlet for a good power supply.

Hopefully the problem is just a blown main fuse inside the microwave. In order to access and check this you will have to disconnect the power cord and then remove the oven from the wall. Then remove the case in order to access the electrical parts inside.

Here is a diagram of the fuse location once you have the unit disassembled:

http://www.appliancepartspros.com/partsearch/frame_diagram.aspx?diagram_id=28700124&pkw_=basket&model_id=5520022&NewWindow=1

The fuse is item number 5001 on the diagram and parts list.

Here is a picture of the main fuse on that model:

http://www.appliancepartspros.com/part_details.aspx?part_id=4440371

Just replace the fuse with an exact match and reassemble. If you tested the old fuse and it was still good, then you may be dealing with a more complicated and expensive fix possibly involving the control panel circuit board. At that point you may want to consider seeking additional assistance or just getting a new oven.

Thank you very much and good luck.

Joe.