thread top ad

Collapse

Announcement

Collapse

READ BEFORE REGISTERING SO YOUR ACCOUNT WORKS

In order for your account to be activated INSTANTLY, your PayPal email MUST MATCH THE EMAIL YOU USE TO REGISTER YOUR ACCOUNT ON THIS FORUM!! If your PAYPAL email address differs from your FORUM email address, your account will have to be activated MANUALLY when a customer service agent gets around to it.

I realize this sucks, and I do apologize.
See more
See less

[SOLVED]820-00165 - No 3.3V on Pin1 of SPI-ROM

Collapse
This topic is closed.
X
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • [SOLVED]820-00165 - No 3.3V on Pin1 of SPI-ROM

    Liquid-damaged. Light corrosion in a few places (see pics) including the area around the SPI ROM chip. SPI_SMC_CS_L is measuring 1.38V instead of 3.3V. PPVRTC_G3H is measuring 3.3V.
    PP3V3_S4 is at around 0.3V, then it slowly drops, and then jumps up to 3.3 for split-second. SYSCLK_CLK25M_X1 is at 0.8V and SYSCLK_CLK25M_X2 is at 0.06V. Because I don't know if you should have a clock at this point I replaced U1900 and Y1905. Not sure where to go next.

  • #2
    I can't see anything on those pictures. Was there corrosion around U6100 area?

    Comment


    • #3
      Ok, I'll have to make a request to Louis to change the image upload converter settings for the forum. The pics are high-res but are getting dumbed down. There is corrosion around U6100. I cropped the pics and uploaded them. Hopefully they're somewhat useable.

      Comment


      • #4
        First clean it off and check all the traces and resistors that are in serie with the data lines.

        Comment


        • #5
          Ok, I don't like to work on them until I clean them in the ultrasonic so any previous notes were after cleaning. I checked all of the lines in that entire area and they're all good. I checked all of the resistor values too and they're fine.

          Comment


          • #6
            Any other thoughts on this? These 2015 Airs are killing me right now.

            Comment


            • #7
              How does U1950 look?

              Comment


              • #8
                Looks good. Diode measurements match a good board. I attached pics of the other 3 spots that got hit.
                Last edited by bjf; 09-22-2016, 07:38 PM.

                Comment


                • #9

                  Comment


                  • #10
                    If that is U1950 in the first picture then it's pretty crusty. I bet the power pin has corroded away under it.

                    Comment


                    • #11
                      Yes, you're right, that is U1950 and it definitely looks like it got hit. I replaced it with a known-good chip. No change.
                      Last edited by bjf; 09-23-2016, 03:11 PM.

                      Comment


                      • #12
                        Was the power pin still good on the board? Many times it is corroded and will not provide good contact.

                        Comment


                        • #13
                          Yeah, everything looks good. It looks like it wasn't hit. I'm measuring 3.42V on the pin. When I measure on Pin 5 (PM_S0_PGOOD) I'm seeing a short pulse up to 3.4V every 5 seconds or so.

                          Comment


                          • #14
                            Is CPU Vcore pulsing too?

                            Comment


                            • #15
                              Yes, it's also going up. It looks like it's hitting a normal voltage when it pulses, maybe slightly high. Somewhere around 1V, slightly higher or lower at times.

                              Comment

                              thread bottom ad

                              Collapse
                              Working...
                              X