Replace the light bulb in model #NN-SN778 purchased a couple of months ago ... there are no instructions in the manual for this

It will do nothing until the clock is set.

Here is the free online manual, but I did not see the light bulb change on my first look through: https://www.manualslib.com/manual/192230/Panasonic-Nn-S446ba.html?page=2#manual

There is a YouTube educational video that may help more: https://www.youtube.com/watch?v=sLidbz2LUtg

I hope this helps you out!

Panasonic Microwave - ConsumerAffairs.com

www.consumeraffairs.com > Homeowners > Microwaves

Rating: 2.6 - ‎53 votes
After looking, door was starting to arc and burn around the edges in three places, ...You can't leave this oven unattended for a minute or you could be calling 911! ... In October 2014 I purchased a Panasonic microwave model NN-SA661S. ... The timeremits "4 beeps" when the time is up; other microwaves, continue to beep ...

[PDF]operating instructions - FTP Directory Listing - Panasonic

ftp://ftp.panasonic.com/microwaveoven/.../nn-sn651_nn-sn661...

PanasonicModels no. nn-sn651b ... nn-sn661s .... Use this appliance only for its intended use as described in this manual. do ... Thank you for purchasing a Panasonic MicrowaveOven. ... you press Start. note: The Glass Tray can turn in either direction. ..... If a pad is pressed and no beep is heard, the unit did not or cannot accept the

We recommend you have an authorized service center location replace the light bulb. Authorized service centers can be found in the below link.

www.panasonic.com/repair
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Hello, I also have a Panasonic Microwave ( model NN-S 564 or 574 ?) They are very similar.
I have just removed the outer cover 5 screws ( unplug of course ) and have located the bulb holder which is a white plastic component with two clips holding the globe, pull it out and remove the two spade clips connected to the globe. The globe will come away attached to a black plastic mount. Next........do the run around to find someone who sells it.
Perth has an authorized distributer/repairer in Myaree whose details I got from Panasonic. He may sell them. otherwise I will try a couple of specialist light globe suppliers I know....PROLAMPS in Belmont and one in BALCATTA whose name escapes me but I have been there before...Hope this helps others.

Martin

Check your manual and see if you purchased the correct type of replacement bulb (wattage).

If there's no obvious removable cover over the bulb (most often on the rear or side) and the owner's manual doesn't address it, then disassembly will be required.

Always unplug a microwave before removing or installing any bulbs.

If it's an over the range type, remove the vent grille across the top and see if bulbs can be accessed there. There may be a panel on the bottom covering the light(s), instead.

If not, chances are you'll have to remove it from the wall, then remove the outer cover. If so, the installation instructions are very handy, and it's best to have two people since the microwave can be heavy and awkward.

You should be able to download your Panasonic owner's manual here.

Once it's out of the wall, the outer cover (wrapper) will need to be removed, just as you'll need to do on a counter top model.

On a counter top model, be sure it's unplugged, but otherwise ignore the instructions above this paragraph.

The screws you need to remove should be pretty obvious, but a special driver (such as a T20H type or GTXH20-100) may be needed.

Be sure to put all the screws back in the right holes, since some may be special grounding screws.

Bulbs can be had in most grocery stores, hardware stores, home improvement centers, and big box or department stores.

Many models use halogen lamps. You must not touch the new one with your bare skin, as the oils will shorten the bulb life.

We're happy to help you with free advice and we'd appreciate your thoughtful rating of our answer.

You can find the instructions for this model here and here.

You should be able to find generic replacement bulbs from local appliance parts stores, home improvement stores, or via a local Panasonic-authorized servicer you can locate here.

Many models use one halogen lamp to illuminate the cooktop and another to illuminate the cavity. You must not touch them with your bare skin as the oils will shorten the bulb life.

We're happy to help and we appreciate your thoughtful rating of our answer.