20 Most Recent Sharp R-308J Microwave Oven Questions & Answers

Many ovens use tamper-resistant screws to discourage people from taking the cover off. It's meant as a safety (that is, fear of lawsuit) measure since microwave ovens use hazardous voltages that can kill you. You can find bits to fit these screws at Home Depot, Sears and many other places if you're determined to get the cover off.

With all due respect, though, you should probably leave microwave service to a professional. As I mentioned above, YOUR OVEN CAN KILL YOU if you don't know what you're doing. That's why Sharp stuck those strange screws in.

Sharp R-308J... | Answered on Jul 08, 2011

Most likely it is the magnatron has gone bad, this or the fan for the magnatron. If your handy you can dissasemble the unit and look for a damaged fan, if none found then the magnatron is most likely bad.

Sharp R-308J... | Answered on May 07, 2011

The Sharp Microwave/Convection oven I have says to touch the Custom Help button, the number "1", then touch the Start Button. To turn off the child lock, press the Stop button.
Or just unplug it, wait 1 minute, and plug in.

Sharp R-308J... | Answered on Jan 02, 2011

Here is a tip that will help you to figure out what is wrong with yourMicrowave Oven....

Microwave Oven Basic Troubleshooting Tips


Sharp R-308J... | Answered on Sep 29, 2010

This is due to the magnatron failing (this is the part of oven that cooks the food!) This is the most likely cause of y isssour oven not heating the food!

Magnatron needs replaced for oven to work again!
Please rate this free soultion!

Sharp R-308J... | Answered on Apr 12, 2009

That would be a problem with the secondary interlock switch (bottom door switch) or its mount.

I would refer you back to the links in my clarification request above.

If a switch is all you need, we offer a universal type for only $5 postpaid which you can order here.

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

Sharp R-308J... | Answered on Feb 21, 2009

We repair those for US and Canadian customers, and occasionally we'll have an Australian customer, but the extra postage is usually prohibitive.

We not only repair them, but we install proprietary upgrades designed to prevent it from failing again.

If you're interested, f
eel free to contact me directly (and please remind me of your full model number) for more information & help.

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

William E. Miller
[email protected]

Sharp R-308J... | Answered on Jan 18, 2009

cockroach may have invaded and damaged the keypad curcuit

Sharp R-308J... | Answered on Jan 16, 2009

hello jeansween ,
can you double check that number please , R-4446 ?


heres a list of sharp microwave owner manuals .

to cancel child lock you touch timer/clock pad, the number 1 and stop/clear pad

hope thats understandable .

Sharp R-308J... | Answered on Jan 03, 2009

You would have to unplug the unit, remove the control panel assembly, then remove the circuit board form the control panel frame.

Then use a soft cloth (not a paper towel) dampened with a non-ammonia cleaner to wipe the debris away.

Do not spray cleaner into the controls.

At our Web site, we have a video available showing how to remove a typical over the range control panel assembly in under 5 minutes.

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

Sharp R-308J... | Answered on Dec 25, 2008

You must clean the bottom rear edge of the LCD glass, both sides of the "zebra" strip, and the contact area of the circuit board with high grade (50% or better) isopropyl alcohol and a clean cloth.

I've attached a photo here, but if it doesn't show up well, you can find it at:


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

Sharp R-308J... | Answered on Aug 09, 2008

I would suspect the thermal fuse / thermal cutout or thermostat (whichever it uses) is open. It is located on or above the magnetron.

When the mag gets too hot, this device protects it from destructive overheating by cutting power to the oven. Hopefully it did its job!!

If you have a Sharp R308 (the heading you posted in) then it will be a thermal cutout.

It should read virtually zero ohms or full continuity, depending on how you check it.

If you or someone you know wants to look into this, we have *critical* safety, disassembly, and troubleshooting info at our site, and our link is at our listing here on FixYa: http://tinyurl.com/yzjozk

You can usually find exploded views and by entering your FULL model number here: http://www.searspartsdirect.com

You should also check the internal fuse, just to be sure.

Please reply with your brand and model number if you need further help or if yours is a different model.

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

William E. Miller, AS-EET
[email protected]

Sharp R-308J... | Answered on Apr 20, 2008

Since you posted your contact info, I have sent you direct e-mail on this.

It sounds like it's repairable with our $39.95 service, but you'll have to decide if it's economical for this model.

Sharp R-308J... | Answered on Dec 08, 2007

You can try and unplug it for 5 minutes, push the on button to make sure it's completely discharged. Then plug it in. If it does the same thing, it's toast. Getting it repaired will cost about the same as a new one on sale.

Sharp Microwave... | Answered on Jan 11, 2020

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