Replacing microwave display?

[Al]

I have a Sharp Carousel microwave, model R-305EW and
the timer/display has developed a problem: part of one of
the LCD-style numbers no longer lights up.

Is it costly to replace the display on this unit? Is it a
relatively easy job for a handyguy with average skills?

 

[Sam Goldwasser]

I have a Sharp Carousel microwave, model R-305EW and
the timer/display has developed a problem: part of one of
the LCD-style numbers no longer lights up.

Is it costly to replace the display on this unit? Is it a
relatively easy job for a handyguy with average skills?

Maybe just a bad solder connection.

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[[email protected]]

Or, it could be a bad connection from the display to the pwb via the
ribbon cable that so many manufaturers use.

Bob Hofmann

 

[[email protected]]

Or, it could be a bad connection from the display to the pwb via the
ribbon cable that so many manufaturers use.

Bob Hofmann

 

[James Sweet]

I have a Sharp Carousel microwave, model R-305EW and
the timer/display has developed a problem: part of one of
the LCD-style numbers no longer lights up.

Is it costly to replace the display on this unit? Is it a
relatively easy job for a handyguy with average skills?

The display is probably fine, likely just needs the connections cleaned
if it uses one of the rubber contact strips, or the solder touched up.
Read the FAQ on microwave safety, then once you've done that this is
most likely something you can fix yourself.

 

[Ray L. Volts]

I have a Sharp Carousel microwave, model R-305EW and
the timer/display has developed a problem: part of one of
the LCD-style numbers no longer lights up.

Is it costly to replace the display on this unit? Is it a
relatively easy job for a handyguy with average skills?

Tossed my 2-yr old Sharp R425E because of a bad display. The replacement
display costs more than what I paid for the whole oven!!

Unfortunately, Sharp (et al) have seen fit to make these displays a
permanent part of the CPU board -- that is, the flex trace ribbon is bonded
in such a way as to make repairs practically impossible. Even if you
_could_ replace only the LCD module, you can't BUY only the LCD module, you
have to buy the entire display/controller assembly.
The replacement cost of your display/CPU board is $118.12 from Tritronics.

Alternatively, if you're a gambler, you can ship your board off for repairs:

http://mem.tcon.net/users/5010/5491/pwbrepair.htm

Even if you're lucky enough that only a very simple repair is needed, at
$32.50 labor plus parts plus shipping... well, which option you choose
depends on how fond you are of your oven I guess.

I purchased that R425E because my old oven was a Montgomery Ward which was
built by Sharp. It lasted 15 years! I was hoping I'd have similar luck
with a new Sharp, but alas they've also decided to produce junk now.

So I thumbed my nose at Sharp and replaced it with an Amana (Maytag), which
is covered with a full 5-year warranty (factory standard, not "extended") on
the display/electronics. That's 4 more years than most manufacturers offer!
I hope this means it's designed to last at least twice as long as the Sharp
did.

Good luck,
Ray

 

[Ray L. Volts]

The display is probably fine, likely just needs the connections cleaned if
it uses one of the rubber contact strips, or the solder touched up. Read
the FAQ on microwave safety, then once you've done that this is most
likely something you can fix yourself.

Sadly, these are not that simple anymore. The display ribbon is glued/taped
to the controller board. There is no solder -- good contact depends on
pressure from the ribbon (it's bent in a "U" loop) and the tape pulling from
the opposing side of the board.
If you peel off the display cable to clean the contacts, GOOD LUCK getting
it realigned with the tightly-spaced traces and maintaining good contact.
Solder can't be substituted for the method used, as the heat will absolutely
destroy the business end of the display cable.
In my case, the display started missing a couple of segments, then a bunch
of them went soon afterward. All the discrete components on the controller
board tested ok. The controller IC still worked as far as the oven
functions were concered. The IC itself isn't replaceable (it's the "black
blob" type), so there are only two options: buy a new board set which costs
more than the oven or buy a new oven.
This is a blatant example of a product designed to ward off repairs and to
have a relatively short lifespan.

 

[none]

Sadly, these are not that simple anymore. The display ribbon is glued/taped
to the controller board. There is no solder -- good contact depends on
pressure from the ribbon (it's bent in a "U" loop) and the tape pulling from
the opposing side of the board.
If you peel off the display cable to clean the contacts, GOOD LUCK getting
it realigned with the tightly-spaced traces and maintaining good contact.
Solder can't be substituted for the method used, as the heat will absolutely
destroy the business end of the display cable.
In my case, the display started missing a couple of segments, then a bunch
of them went soon afterward. All the discrete components on the controller
board tested ok. The controller IC still worked as far as the oven
functions were concered. The IC itself isn't replaceable (it's the "black
blob" type), so there are only two options: buy a new board set which costs
more than the oven or buy a new oven.
This is a blatant example of a product designed to ward off repairs and to
have a relatively short lifespan.

I've got a Sharp with the same problem, bad LCD display unit.
Like you said they want way too much for a replacement. In my case
nearly 50 bucks just for the crystal module.
all else works fine on the oven, you just have to push the buttons
carefully to get whatever time and cooking level desired.( I'll find a
donor some day with a dead magnetron that'll hopefully have a good
display. Untill then it's push the buttons slowly and carefully.)

 

[James Sweet]

I've got a Sharp with the same problem, bad LCD display unit.
Like you said they want way too much for a replacement. In my case
nearly 50 bucks just for the crystal module.
all else works fine on the oven, you just have to push the buttons
carefully to get whatever time and cooking level desired.( I'll find a
donor some day with a dead magnetron that'll hopefully have a good
display. Untill then it's push the buttons slowly and carefully.)

Is there room to drill a hole in the board on each side of where the
ribbon connects? If so you could cut a little block of aluminum, file it
so it has a ridge down the middle, then thread holes in the ends and
screw it to the board so the ridge presses on the ribbon and holds it to
the contacts.

 

[Ray L. Volts]

Is there room to drill a hole in the board on each side of where the
ribbon connects? If so you could cut a little block of aluminum, file it
so it has a ridge down the middle, then thread holes in the ends and screw
it to the board so the ridge presses on the ribbon and holds it to the
contacts.

Should be room on the later model Sharps. As these are layered boards, be
careful with the locations of the clamp holes. If necessary, use a plastic
strip for the clamp, held down with nylon thru screws (or rivets) or plastic
spacers as feed-thru bushings for the metal screws if the nylons aren't
available.

From what I've since read on Sharp ovens, problem contacts don't appear to
be the common failure mode. Still, for those lucky individuals where the
only prob may be dirty or loose contacts, this is a perfectly acceptable
fix -- actually, it would be a much superior method over the crummy original
design!

 

[Al]

Thanks for the various suggestions to my original post.
Two question: (1) How do I access the display on this model?
(2) Assuming I don't want the expense of a new board and
that I lack the expertise to perform some of the procedures
listed above, what's one "simple" fix I might be lucky enough
to encounter when I get a look at the display? Dust on the
ribbon, haha. Thanks.

 

[James Sweet]

Thanks for the various suggestions to my original post.
Two question: (1) How do I access the display on this model?
(2) Assuming I don't want the expense of a new board and
that I lack the expertise to perform some of the procedures
listed above, what's one "simple" fix I might be lucky enough
to encounter when I get a look at the display? Dust on the
ribbon, haha. Thanks.

You might have some luck wedging something between the display and the
board to put pressure on the ribbon, hunk of styrofoam or something.
Never seen inside that model so I can't offer specific help though.