Announcement

Collapse
No announcement yet.

Suspect Bad PS Apple AcBel API 1PC36

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

    #61
    Re: Suspect Bad PS Apple AcBel API 1PC36

    Ok ... tell me how to safely jump off a cliff and I'll probably do it ...

    This may take me a bit (fitting it in around some other 'duties') but think I understand the 90%.

    Soldering to Pin2 would be next to the square solder pad. (?)

    Found a piece of 24ga wire should be good (better than the 16ga next choice)

    Need to ask (because I've wondered) - I did the cap soldering with a chisel tip and wonder if I should have used a needle tip. The chisel tip seems to melt the board solder 'almost' before it touches (fast at any rate)?

    Measuring the 3.3/5/12 would be as done when checking voltages initially (using a pinout diagram and instructions)?

    Comment


      #62
      Re: Suspect Bad PS Apple AcBel API 1PC36

      Reporting:

      5v test(s) ... pins 1 and 3 ... 4.7v and 4.1v

      12v test(s) ... pins 10 and 24 ... both 8.8v

      3.3v test ... pin 6 ... 3.3v (pins 17, 18 and 19 also tested 3.3v)



      EDIT: Daughter board 5th pin tested ~2.4v occasional drop to ~1.5v
      Last edited by buz; 04-26-2011, 06:40 PM.

      Comment


        #63
        Re: Suspect Bad PS Apple AcBel API 1PC36

        oops .... 5th pin results above was jumpered

        unjumpered 5th pin tested 4.4v

        Comment


          #64
          Re: Suspect Bad PS Apple AcBel API 1PC36

          >>Soldering to Pin2 would be next to the square solder pad. (?)<<

          Pin 1 on *most* IC's and such devices is *usually* indicated by a square solder pad.
          It is also *usually* indicated by a dot or dimple on the device itself.
          (see pic 1)

          Pin 2 of M8 is the round pad next to Pin 1 (the square pad on M8). You just tested it yesterday. (see pic 2)

          The 2.4v on DB pin 5 has me concerned as it may not be low enough to fully turn on the opto. The 1.5v is the IC trying to start up and check the voltages.

          I need you to solder the 2 resistors in that package together in parallel. (see pic 3)
          This makes the resistance 1/2 of 1kΩ or 500Ω. That should provide a low enough resistance path to enable the opto fully.

          Rerun the prior test and repost the voltages.

          Toast
          Attached Files
          Last edited by Toasty; 04-26-2011, 08:43 PM.
          veritas odium parit

          Comment


            #65
            Re: Suspect Bad PS Apple AcBel API 1PC36

            Pin 5 jumpered ... 1.0v - 1.6v

            unjumpered .... 5.56v

            Comment


              #66
              Re: Suspect Bad PS Apple AcBel API 1PC36

              Other voltages 3/5/12...?
              veritas odium parit

              Comment


                #67
                Re: Suspect Bad PS Apple AcBel API 1PC36

                Pin 1 - 4.75
                Pin 3 - 4.1
                Pin 24 - 8.9
                Pin 10 - 8.9
                Pin 6 - 3.3

                with doubled resistor

                Comment


                  #68
                  Re: Suspect Bad PS Apple AcBel API 1PC36

                  Good. Those voltages are a clue that there is something wrong with the 5v/12v line and that's why the supply is not running. Something is not coming up strong enough to run that section. It could be on the input side or one of the diode packs has failed.

                  Let me get some other things together for you to test.

                  Good work!

                  Toast
                  veritas odium parit

                  Comment


                    #69
                    Re: Suspect Bad PS Apple AcBel API 1PC36

                    Thank you a million for hanging in here w me - hate to say it but it's kinda fun on this end.

                    Comment


                      #70
                      Re: Suspect Bad PS Apple AcBel API 1PC36

                      I figured I should be as sure as possible about my soldering to either eliminate it as a current problem or call it 'good enough'. I know it needs improving. The photos are of what I think is the worst of it.

                      Hate to be chasing other troubleshooting unnecessarily.
                      Attached Files

                      Comment


                        #71
                        Re: Suspect Bad PS Apple AcBel API 1PC36

                        Set DMM to Diode Check function.

                        PSU unplugged and no jumpers.

                        Do the following and hold each for 10 seconds before you take a reading.

                        With DMM black lead on ground / black / negative at mobo plug:
                        5v / red
                        12v / yellow

                        -then reverse-

                        With DMM red lead on ground / black / negative at mobo plug:
                        5v / red
                        12v / yellow

                        Report readings.

                        Toast
                        Last edited by Toasty; 04-29-2011, 01:20 AM.
                        veritas odium parit

                        Comment


                          #72
                          Re: Suspect Bad PS Apple AcBel API 1PC36

                          Black to pin 12
                          Red to Pins 10 / 21 / 22 / 24
                          Reading = 189
                          Reversed = 155

                          Black to Pin 12
                          Red to Pins 3 / 4 / 15
                          Reading = 23
                          Reversed = 23

                          Comment


                            #73
                            Re: Suspect Bad PS Apple AcBel API 1PC36

                            Please Stop using pin numbers. I have to go look this up -every time-.

                            Use them the way I gave them, please 12v/yellow - 5v/red

                            AND, you can do it right on the board without using the plug.

                            Saying that, the 189 looks suspicious as I get .250

                            Your meter may vary, but isn't there a decimal point? Or a zero in front of the 23?

                            Ok. Time for pics to mark next locations.

                            Toast
                            veritas odium parit

                            Comment


                              #74
                              Re: Suspect Bad PS Apple AcBel API 1PC36

                              Ok - sorry - had no idea it was a problem and understand.

                              I retested at the board and received the same results - no decimals but there is a zero in front of the 23 so - 023.

                              My novice is showing.

                              Comment


                                #75
                                Re: Suspect Bad PS Apple AcBel API 1PC36

                                Did you ever get the solder-wick? The next test will require unsoldering some leads so the items can be tested "out of circuit", but not off the board.

                                I suspect one of the 12v dual-Schottky diode packs to be leaky.
                                This PSU does not have a pi filter on the 12v line, so I'm doubting it's the 12v cap (2200uF/16v) you replaced.
                                Last edited by Toasty; 05-03-2011, 01:10 AM.
                                veritas odium parit

                                Comment


                                  #76
                                  Re: Suspect Bad PS Apple AcBel API 1PC36

                                  Yes - got the wick, .10" blue label. Ready when you are.

                                  Comment


                                    #77
                                    Re: Suspect Bad PS Apple AcBel API 1PC36

                                    Here we go. See the pics as to what these devices are and where to unsolder two legs of each. Wiggle the leads around slightly to make sure you don't have contact to the foil traces. You can use the continuity test on the meter to be sure.

                                    Then test them as individual diodes (4).
                                    They should all give the same readings.
                                    The odd ball will likely be the bad one.

                                    Toast
                                    Attached Files
                                    veritas odium parit

                                    Comment


                                      #78
                                      Re: Suspect Bad PS Apple AcBel API 1PC36

                                      Took me a bit to figure out the testing but think I got it. The picture shows the 12vShottky and hoping my diagraming isn't too hard to follow.

                                      I number the connections 1, 2, 3 across the 'top' and 4, 5, 6 across the 'bottom' as viewed from the pictures

                                      Tested 1 to 2 and 4 to 5, both read 159

                                      Tested 1 to 3 and 4 to 6, both read 0
                                      Attached Files

                                      Comment


                                        #79
                                        Re: Suspect Bad PS Apple AcBel API 1PC36

                                        Seems like the 0 readings indicate you still have contact with the foil.

                                        Should have 8 readings. 4 diodes X 2 readings for each.

                                        Start with black on center pins (cathode) and red (anode) on outer. Then reverse the leads to red on center and black on outer.

                                        The desoldered pins should be "loose" in the hole and you should just be touching the pin(s) with the probe on those. Push them a bit to see if they wiggle and the reading changes.

                                        1 - 2
                                        2 - 3

                                        4 - 5
                                        5 - 6


                                        then:

                                        1 - 2
                                        2 - 3

                                        4 - 5
                                        5 - 6


                                        Does that make sense? Sometimes I assume too much.

                                        Toast
                                        veritas odium parit

                                        Comment


                                          #80
                                          Re: Suspect Bad PS Apple AcBel API 1PC36

                                          Actually, unsolder the remaining two pins. If everything is good, the first 4 readings should match and the second 4 should read infinite (open).

                                          0 = zero ohms, as if the meter leads are touched together

                                          Infinite would be as if the leads were not touched together. The meter should not register anything.
                                          Last edited by Toasty; 05-03-2011, 05:02 PM.
                                          veritas odium parit

                                          Comment

                                          Working...
                                          X