[fix]

Hi all

A friend of mine asked me to take a look at her camera. LCD do not working properly.
First I think it's broken. Then I keep MENU-button down while start up the camera. LCD show: Pentax K-m. VER: 1.0
Everything else seems to work.
I put memory card inside and I can take pictures, but lcd is blank.
So I try to find solution over the internet, but no luck.
I changes battery, cleaning the contacts. No changes.

Then I found new firmware. Insert it to memory card on pc.
Then insert memory card to camera and turn it ON. LCD seems to work. It show me menu where I choose or not new firmware.
New firmware went in and all the time lcd showing statusbar to indicate to process.
I turn camera OFF and ON. No change. LCD is blank.

I keep MENU-button down while start up the camera. LCD show now: Pentax K-m. VER: 1.11
I switch memory card to lock-position. LCD show now: card is locked.
That's all i can do.

Anyone else same problems?
Any thoughts, what I can try?

Is there maybe some micro-switch, what is stuck...

And sorry my spelling

[bobhoskin]

Hi,
try checking if it's a bad contact of the backlight of the LCD, seems like when you keep pressing the MENU button on startup, you move contacts behind....
to verify, try to press the menu button in different ways (when it's on with the lcd not working)
Otherwise you can try.... turn on the camera, and try look better at the LCD with strong light around, or better take a tourch and make light on it, you should see normally menus etc... so you know it's the backlight with problems.


otherwise I think can be something wrong with the mainboard - - -

[fix]

Thank's for your quick reply.

You are right! There is contact failure somewhere.

First i try to find some image to lcd with torch but nothing.
I removed the bottom plate and all the screws and carefully twisted and pushed
the frame near lcd. I inserted the battery and make testing but nothing.

After that i twisted and pushed the back frame near SD-card and suddenly it works!
So i don't know exactly where the fault was.
It seems little bit tricky to disassemble lcd...

When i put the screws and tight them, lcd is again blank.
I must keep hunting the contact failure.

[wlachan]

Sounds like failed solder or oxidized contact.

[bobhoskin]

Sure, oxidized contacts are frequently a problem.
The best thing to do will be open the back of the camera, and remove the back lcd/buttons connector and plug it in again, doing so for about 2-3 times will clean the contacts by sliding, but you need to remove a lot of thing to access there (bottom plate, rubber grips, top flash cover, a lot of screws, and carefully bend the back plastic etc..........)

I see the back of the K-m it's identical to the K-r, and I think the connector will be in the same place:

[wlachan]

For a problem like this, DeoxIT will do wonder (or WD40 too).

[fix]

I removed the outer shells and now cleanup all the connectors.

And back plate seems to be identical. (I try to put a image, but it vent to some approval)
i'll tell how to go

[fix]

I think I found the place, which causing the problem on the screen.
It is a button into middle of the ON/OF-switch. That button which take the picture.
When I lift the top shell near the ON/OF-switch or loosen the screw, lcd works fine.
It is soldered to the flex-cable.
I bend little the top-plate of the button and now it seems to work. It don't show anything, when you focus.
And there is no preview-image.
I put all together and testing and hope that helps for now.

So the camera was focus-mode? all the time, am i right?
I don't know how lcd would act when it push a little.

I took picture of the problem


I thank all for your help :-)

[bobhoskin]

hhmmm, seems nonsense and strange that button can cause the problem, I can think when you was moving the top-shell you move either the large flex from the top circuit to the back mainboard (the connector up over the LCD connector), that have a lot of pins to clean....

You mean now the camera it's in Auto-focusing all the time? I don't have the K-m, but I think it's not correct (if maybe has not been set on some Menu option). It's like the shoot button it's half pressed all the time.

[fix]

hhmmm, seems nonsense and strange that button can cause the problem, I can think when you was moving the top-shell you move either the large flex from the top circuit to the back mainboard (the connector up over the LCD connector), that have a lot of pins to clean....

You are probably right. But that is the only place, what gives something response.


You mean now the camera it's in Auto-focusing all the time? I don't have the K-m, but I think it's not correct (if maybe has not been set on some Menu option). It's like the shoot button it's half pressed all the time.

I mean before. Lcd was blank all the time and when I release top-shell screws or i lift it near to button, lcd works.

Then i was bending carefully to the buttons top-metal sheet and now lcd works.
Lcd goes blank if i button is half-pressed. Is this make any sense?

But i take a hint and i clean more accurate :-)

[wlachan]

I don't quite follow how the button could be the source of problem, but if that button is found defective, you can get a new one from Pentax and solder on.

[art_oliver]

Hi,

Did you find the cause for the problem ? Maiboard failure ? I'm actually in the same boat ...

Cheers

[art_oliver]

Take a look here:

Pentax K-m LCD problem - PentaxForums.com

It works for me

Chees