replacing the cf-29 touchscreen

Hi everyone I'm new here. Last year got into cf-29 craze. Recently I fitted extra ram, i did the dvd burner mod, i got a chicklet backlite kb and everything went fine in fact its easy just take time and reverse engineer it in your head a bit. Now those mods were easy but now i have a problem I have a slightly harder mod or fix to do and that is to fix a "funny" touchscreen

the problem is as already talked about in other threads, the ts courser is erratic in the horizontal movement mainly i think and it comes and goes all the time calibration is here and there as well

I opened the screen up and I took my time as I had no experience and there is no howto or sticky on this here. I fiddled around with the ts pcb and with the cables carefully nudging them and it has no affect on the position of the courser on the ts when pressing on the screen as you would.

This indicates to me that it is the touchscreen at fault and is probally due to build up and drop off of voltage etc. inside the touchscreen guts.

So I have got that far. Iam stuck. I cannot figure out how to remove the both ts pcb cables and I have only being able to tilt the lcd panel up a little bit to see the touchscreen under it.

Question 1 : how do you remove the tiny pcb cables I cannot see how these clamps work

Question 2 : I could not find any ref to a touchscreen part no for my cf-29htlgzbm ( mk3)

Question 3 : Is there any tips for the rest of the work to be done after lifting up the lcd panel assuming I have a new touchscreen ?

Thanks

also i should add that this problem is only happening on the right side of the screen. i've just read toughbooks post funny that there would be another touchsreen post when there wasnt one in ages. this cf-29 has had this prob ever since i bought it on ebay. i contacted the seller and told him i'd charge him for the parts.

 

See the newly added post in the CF-29FAQ.... I had a similar issue and Teo (Ohilip) suggested a crushed toothpick to dig out crap between the frame and the LCD.... DO THIS CAREFULLY.... I banged the end of the toothpick on an anvil with a hammer to get it to 1/2 a mm or so....

Try this first and report back.. Then we'll talk swap... It's easy... It takes 15 minutes at most!

 

Boy, you gotta love a computer where you can use an anvil to fix it!

 

If only I could reach in there but I cannot lift the lcd panel up fully with the cables connected I havent figured out how to release the clamps on that ts pcb

 

I believe the clamps you are talking about just come right off. They just "snap" into place. I can't think of any other "clamps" that exist on the board.

 

There are no clamps on it. All the connection inside are plug in, just pull it hard on the connector but gently not to damaged the cable wires and take off all the tape coz sometimes its hide on it. Remember that there are two plastic separator below the LCD. The LCD connector is also the same its plug in. Hope it help.

Edit: hold on, i want to clear this out. Are you talking about the whole set of LCD panel? Case, hinges, everything?


ohlip

 

Yes, I have already figured out how to remove the kb bezel, then the hinge protectors, then the screws on screen case leaving the screws which you dont have a screw driver for in ( star shaped). Then lift up the screen case and you see the white corner seperators and rubber bumpers etc. I have figured all that out but I have not gone under the lcd panel to the touchscreen panels yet.

 

So you want to replace JUST the LCD? Or the whole LCD assembly?

First... You MUST have a good set of precision screwdrivers to do this... Wiha makes the best I have found so far. If you try this with Craftsman tools you WILL strip screws. You may get it apart and back together once... But then everything will be stripped!

The LCD assembly is an easy swap... You need to take off the four screws that holds down the keyboard top... Then the four screws on each of the hinge covers. Then CAREFULLY fold the keyboard onto the palmrests and remove the 5 small silver screws and remove the cover. You can then unsnap the keyboard ribbon cable connectors and remove that... It isn't totally necessary but it makes it a lot easier not having it dangle.

On the right side of the hinge is a black plastic housing that slides down into the laptop case. This routes the wiring from th LCD down into the laptop body. This can be gently worked loose. You will also need to unsnap the black and white Wifi wires on the PC board to the left. The LCD cables just push into the mobo on the back center right. Be VERY careful popping them out as there are many FINE wires going into the connectors.

With the hinge covers off you can start to feed the wires back up through the slot in the back. With the wires out or at least loose you can then remove the screws that hold the LCD in place. (Two on each side) You should be able to take it all off now.

With this, if you want to replace just the LCD or touchscreen, you will need to unscrew the screws on each side of the LCD... Depending on what you want to do now is up to you. If you want to replace the touchscreen or the just the LCD you will need to separate the two. BE CAREFUL when doing this. The wires on the connectors here can be almost as thin as a hair and can be pulled out or broken quite easily.

Of course you want to have a "Clean Area" set aside for doing this unless you have done this enough times. I can swap out an LCD in 5-10 minutes... But I have done it for years now. It may take you a few hours... Take you time, remember where every screw, wire and bumper goes. Take a few pics with your cell phone camera or digital camera to make sure you can put it all back together the way it is supposed to go.

If you have any other questions... Let us know. There is usually someone on here 24/7... Especially on the weekends!

EDIT: Is the pointer erratic using both the touchscreen AND the touchpad? Or is it one or the other?

 

No Its just the touchscreen I have not any problems with the lcd panel just the touchcreen panel

the touchscreen is erratic in horizontal movement, this is true for both the top and bottom of the right side of the touchscreen panel. The cursor does not move in erratic diagonal directions.

The touchscreen will point right one minute and another it is erratic

The mouse has no involvement in the problem.

 

So your saying all I have to do is pull on the ribbon cable connecting the touchscreen pcb (the smaller board in the plastic holder on the right side of the assembly) to the touchscreen i.e the touchscreen panel under the lcd panel

Then I can get at the touchscreen panel and I can replace it if it need to be replaced

However I would like to try the tooth pick thing first please explain it to me ?

And finally while your there do you have the part number for a replacement touchscreen for my mk3

Regards
Paul

 

I can almost guarantee that it is not your touchscreen panel. They rarely go bad unless they are shattered. It is probably something that is stuck between the LCD frame and the touchscreen. If you read the CF-29FAQ... I explained in there what you need to do.... You basically lightly crush the end of a toothpick and run it around the inside of the frame... Just go lightly. Most likely your issue will be on the bottom since gravity naturally pulls stuff in there...

 

Nice one, I will try that as soon as I have available time again......

 

I did the tooth pick thing. I got the thin toothpick and ran it between the frame and touchscreen after opening the screen case. I got out as much as possible the sticky black seal thing made it hard to get it all. I also carefully used a vacuum cleaner to aid removing the dirt

I also cleaned from the exterior of the touchscreen (from the front of the screen i.e the part you touch and the frame) just by using the toothpick and running it around the edge of the touchscreen.

The difference now is that the coursor is moving "sometimes" in an erratic vertical motion instead of horizontal motion.

Things are generally the same with the touchscreen. I turn on the computer the touchscreen is calibrated but after I start using the touchscreen I notice that the coursor has lost its calibration at different parts of the screen.

It is usually good on the lower left of the screen. The mid right, top right and top left are out of calibration when the problem occurs

Tapping with my hand from the other side the touchscreen has no effect

Increasing finger pressure or decreasing finger pressure has no effect.

Its almost as if when the touchscreen is warmed up or used for a few minutes it loses its calibration and "can be" erratic at these times as well.

 

Hmmmmm.... You might try just removing the touchscreen pane and having look to see if anything is embedded in the foam tape that goes between the frame and the screen. The fact that the "Erratic motion" changed direction leads me to believe that is what it is.... Perhaps the toothpick pushed it further down in.... Or part of the toothpick broke and is stuck between.... You shouldn't have gone down as far as the foam I should think...

 

Ireland,
At least your efforts seem to have proved your problem to be something mechanical like dirt, not a software or hardware issue.
CAP

 

What he said!

 

I have not had any trouble since I re- calibrated it last night after it went erratic when I was finished the work with the toothpick.

Note: maybe the dirt is now beyond the margin of the calibration

So fingers crossed that it will be ok if it starts up again I will do a full clean.
Can you explain how to remove the other panels other than the lcd panel ?

And yes some of the dirt got stuck in under it and I could'nt remove it with the toothpick.

Certainly it does look like a dirt problem right now.
It does tell me how important it is to clean the toughbook when it gets dirty.

However I am still not convinced because the coursor was not going in one particular direction as to towards dirt or something.

Thanks for the help touch wood it will stay good

 

What panels do you want to remove? They are all fairly easy to remove.

 

The touchscreen is gone out of calibration again. I havent noticed any erratic movements.

Please tell me how do I remove the touchscreen panels. I know everything up to removing the lcd

I will have to clean the touchscreen properly then decide on what to do.