Announcement

Collapse

Announcement

Welcome to the NEW iPad Rehab Forum! Everyone is welcome to read posts and learn for free. If you'd like to post your own question on the forum, please click "register" above or go here: http://forum.mendonipadrehab.com/register to enroll as a paid subscriber for $29/mo for unlimited access to our forum support and private signature failure section.
See more
See less

iPhone 6 Plus No touch.

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • iPhone 6 Plus No touch.

    Hi, I'm Trying to repair an iPhone 6 Plus pcb with no touch, the board has no prior repair but has a replacement LCD attached when it came in and it came in with no touch. I ruled out LCD, tried 3 different LCD still with no touch. Then I probed around the digitizer connector (J2401) on diode mode and found some of them doesn't match ZXW or to my known good and arrived to the conclusion that that U2401 is faulty, Replace U2401 and made an m1 pad jumper since the pad was pulled, after all that I probe again on my connector and all is now a match on ZXW and to my know good BUT i still have no touch. Does anyone know what causes this no touch ? I can't seem to figure this out.
    GHI888
    Friendly Contributor
    Last edited by GHI888; 11-27-2017, 03:03 AM.

  • #2
    I would double check Meson placement again

    Comment


    • #3
      Originally posted by tinker_techguy View Post
      I would double check Meson placement again
      I did even gave it a nodge. Im pretty sure it wass place properly.

      Comment


      • #4
        Originally posted by tinker_techguy View Post
        I would double check Meson placement again
        and everything around it

        Comment


        • #5
          Check bottom left screw hole. Long screw can also take out touch from that hole.

          Comment


          • #6
            Originally posted by tinker_techguy View Post
            I would double check Meson placement again
            Will do, Thanks!

            Comment


            • #7
              Originally posted by tinker_techguy View Post
              Check bottom left screw hole. Long screw can also take out touch from that hole.
              Thanks! It has a long screw damage, can't believe I missed it! I looks like im going to do trace repair...

              Comment


              • #8
                Your thought process so far was right on track. When you saw that M1 pad came off with the chip---that seals the deal. This board HAD no touch because of classic touch disease. 90% of the time, replacing meson with M1 jumper will solve a board like this---however in your case it did not. Since you know for sure that you had a meson defect, and you replaced meson, the next step is----replace meson again! Today I messed up a tristar job somehow. It seemed fine, but there must have been some speck of something that was keeping the chip from making a connection. Because the symptoms were so classically tristar, I replaced it again and it solved.

                iphone 6 left screw LSD causing no touch is possible, but rare--it would have to be very severe on one side affecting third layer traces, and yet also minor on the other side because it did not tear lcm_pwr_en or ap_lcm_reset since you have chestnut function since you can see image. Not every screw hole impression actually tears lines. This is a judgement call since only you have eyes on the board. Does the LSD look severe enough to fracture third layer? If yes--go after LSD. If not---go after meson and surrounding components like the trailer park caps that can also cause no touch.

                Comment


                • #9
                  Originally posted by Jessa_the_Professa View Post
                  Your thought process so far was right on track. When you saw that M1 pad came off with the chip---that seals the deal. This board HAD no touch because of classic touch disease. 90% of the time, replacing meson with M1 jumper will solve a board like this---however in your case it did not. Since you know for sure that you had a meson defect, and you replaced meson, the next step is----replace meson again! Today I messed up a tristar job somehow. It seemed fine, but there must have been some speck of something that was keeping the chip from making a connection. Because the symptoms were so classically tristar, I replaced it again and it solved.

                  iphone 6 left screw LSD causing no touch is possible, but rare--it would have to be very severe on one side affecting third layer traces, and yet also minor on the other side because it did not tear lcm_pwr_en or ap_lcm_reset since you have chestnut function since you can see image. Not every screw hole impression actually tears lines. This is a judgement call since only you have eyes on the board. Does the LSD look severe enough to fracture third layer? If yes--go after LSD. If not---go after meson and surrounding components like the trailer park caps that can also cause no touch.

                  Hi! Jessa Big fan here! I'm really glad you put up this forum.BTW I just dug the LSD and no torn trace, all traces are good, So Replacing Meson it is.
                  GHI888
                  Friendly Contributor
                  Last edited by GHI888; 11-27-2017, 02:58 AM.

                  Comment


                  • tinker_techguy
                    tinker_techguy
                    Friendly Contributor
                    tinker_techguy commented
                    Editing a comment
                    So there was long screw damages on the bottom left hole? How did you know what trace was for touch to be certain it was good? The touch trace in this hole is on the 3rd layer, but there is a small via on the second layer next to this hole.

                    Update**

                    You could verify to see if touch trace is bad by continuity mode from the FPC connector to that via dot next to the hole. Use ZXW if you have it and find it. I don’t remember what the line is called. I just remember where it is and not at office.
                    tinker_techguy
                    Friendly Contributor
                    Last edited by tinker_techguy; 11-27-2017, 03:10 AM.

                  • GHI888
                    GHI888
                    Friendly Contributor
                    GHI888 commented
                    Editing a comment
                    The LSD was not that severe and there is no visible damage on any of the traces. btw LSD was on the Lower right side of the board sorry I might not have mentioned it.

                • #10
                  Originally posted by GHI888 View Post
                  The LSD was not that severe and there is no visible damage on any of the traces. btw LSD was on the Lower right side of the board sorry I might not have mentioned it.


                  Ok than that rules out long screw taking out touch if it’s in the right side.

                  I would re do meson

                  Comment


                  • #11
                    I HAVE TOUCH! Thank you guys! really appreciate it, .

                    Comment


                  • #12
                    Originally posted by GHI888 View Post
                    I HAVE TOUCH! Thank you guys! really appreciate it, .
                    Yay! Solved one!

                    Comment

                    Working...
                    X