thread top ad

Collapse

Announcement

Collapse
No announcement yet.

820-2915 - not detecting battery

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

  • 820-2915 - not detecting battery

    Hi guys ,
    need help on this board . it is running fine on the charger but does not detect battery , i have checked the resisitor r5281 and r5280 , the both are showing 2.0k
    there is no short to gnd on SMBUS_SMC_BSA_SCL and SMBUS_SMC_BSA_SDA. i have already changed the isl but no change . the strange thing which i have noticed is
    the q7030 getting extremely hot . i replaced that aswell but no luck .
    ( it has a cross on battery icon hence not detecting the battery )
    plz advise thanks
    Last edited by techrepair; 05-25-2016, 06:04 PM.

  • #2
    Try with another known good battery.... If remove battery, Q7030 still getting hot???? What voltage do you have on SMBUS lines??

    Comment


    • #3
      hi ,
      thanks for the reply , Q7030 is getting hot without the battery . i will check the voltages and update thanks
      Last edited by techrepair; 05-25-2016, 06:49 PM.

      Comment


      • #4
        Is 12.6V on F7040 stable????

        Comment


        • #5
          How did this come to be? Someone replacing the battery and shorting pins? Water? Out of nowhere?

          There are four items in this circuit. The battery, the U7000, the SMC, and the battery indicator/sleep sensor/LED thingie on the side.

          You replaced the U7000. Unplug the sleep sensor/battery indicator thingie. Does it see the battery?

          If not, try good battery.

          Does it still not see a battery?

          If it doesn't, at this point, it is the SMC.

          But give some better history.

          Comment


          • #6
            hi Aprendiz and Louis ,
            Thanks for the update and information , it came from another repair shop , i am attaching some pics , please have a look , i think on Q7030 the voltage should drop to 12.6 v but it does not drop and stays between 17 to 18 volts on pin 1,2,3 and also gate voltage at pin 4 . it gets hot without the battery . No shorts to ground on battery pins apart from the 3 ground pins which i suppose are meant to be that way . on the smc line resistors the voltages are 3.4 volts and on f7040 the voltage is between 17-18 volts which i suppose should be less .

            please look at the attached pics , I found these solder blobs but they are not shorting anywhere until there is a track here which goes to smc but i doubt that . Machine is not even slow . this one is proving to be difficult and beyond logic .
            i have cleaned the solder blobs and replaced the q7030 , changed the caps around q7030 . No idea but do not want to give up .
            Attached Files

            Comment


            • #7
              Q7030 getting hot can only really be caused by a dead 6259, bad q7030 or 7035 or the traces to the gates of them. Battery detection will probably be 6259 or SMC.
              If you remove the 6259 it should still work on the battery if it is recognized.

              Comment


              • #8
                thanks for the response ,
                q7030 kept on getting hot , this time rather than replacing q7030 first i replaced the isl and then replaced the q7030 , now it is not getting hot but now on battery plugged in i was getting very low output from d6990) and after replacing d6990 i have 3.42 volts but the board does not start ( battery not recognized) . As there is no short on smc data lines i think smc itself is faulty but finding a working smc from another board and replacing it is a torture .

                Comment


                • #9
                  it is, and you're going to go do it anyway for practice and report back how it went.

                  Comment


                  • #10
                    without a doubt

                    Comment


                    • #11
                      hi,
                      that board went away but i am replacing the smc on 820-2838-a, i have removed it successfully but now i am unsure that either an smc taken from 820-2327 will work on 820-2838-a i or will not work ?
                      logically the new smc's can be programmed differently so no idea. Also i need to replace smc on a1466 but do no have the same board as donor . so kindly advise as which smc's are compatible . thanks

                      Comment


                      • #12
                        Get the exact SMC from a donor board, do not try to swap them around too much wasted time.

                        Comment

                        thread bottom ad

                        Collapse
                        Working...
                        X