Hello, i've got an 820-01987 from a friend who had spilled diet coke on the computer. I am a novice and I have not repaired any other macbooks, but I feel like i have a decent fundamental and practical knowledge of electronics. So. please excuse my ignorance. I've done research for a few days and I'm stuck. Ill try to start from the beginning, and be as thorough as possible.
I have found corrosion around these components/areas
Either way, I had cleaned up the corrosion and reflowed everything aside from the connectors.
Currently, i am drawing 20v and the amperage fluxuates. with the board alone I'm getting up to .525A, and then it drops to about the .386A before cycling again from 0a..
With everything connected, i get 20v and about 3a. It seems to be charging the battery.
I get no caps lock light activity, but i do get trackpad click. No backlight. I can't see an image. I don't have a thermal imager but i can't feel anything hot.
I've tried putting the computer in DFU rest mode multiple times, but I can't get it to show in Apple Configurator. I've tried two different cable, and both USB C ports on both machines. I have tried it with the battery disconnected and connected. I am using the L Control L Option R Shift for 7 seconds, and then the same but with the power button. The computer seems to be responding to these inputs. It will start and stop the fan. The fan won't run continuously iirc.
I believe all my main power rails are present and within the specified range. I used this , along with other forum posts to guide me on what i should be measuring and how much voltage i should expect. I assume with the chart i linked, if any rail is missing, rails that occur later in the list would not be present, right? Maybe this is where my ignorance sets in... I haven't recorded any of the voltage from the power rails that i checked, as i didn't notice anything wrong with them.
I did check my CPU core voltage, PPVCC_S0_CPU, and I think i am getting a high voltage. I'm getting .8 v and its not stabilizing to .6-.7v, which i had read is the proper voltage. This voltage will return to 0 with the amp cycle of the board. It seems to come on and off when current draw is at or about .3a. CPU is warm.
I read that these boards will not boot without a battery. I'm not sure if DFU mode is accessible without the battery installed. With the board on the bench,no battery, I don't measure any voltage at SoC_DFU_STATUS. I don't know how to get to this test point without installing the board. Maybe the battery is dead and it needs to be charged? With corrosion previously present at j6941, could this have damaged the battery? should I try a new one from Amazon to see if i can get it to boot?
This is where i'm stuck. Being a novice, I don't know the normal operation state of these boards and i find it difficult to find information of that.
To me, the board seems like it wants to boot. Maybe there is something wrong with my t2.
Apologizes if this was long-winded or confusing. Any help or guidance would be greatly appreciated.
I have found corrosion around these components/areas
- u3750
- q7660
- q7702
- j6001
- j6951
Either way, I had cleaned up the corrosion and reflowed everything aside from the connectors.
Currently, i am drawing 20v and the amperage fluxuates. with the board alone I'm getting up to .525A, and then it drops to about the .386A before cycling again from 0a..
With everything connected, i get 20v and about 3a. It seems to be charging the battery.
I get no caps lock light activity, but i do get trackpad click. No backlight. I can't see an image. I don't have a thermal imager but i can't feel anything hot.
I've tried putting the computer in DFU rest mode multiple times, but I can't get it to show in Apple Configurator. I've tried two different cable, and both USB C ports on both machines. I have tried it with the battery disconnected and connected. I am using the L Control L Option R Shift for 7 seconds, and then the same but with the power button. The computer seems to be responding to these inputs. It will start and stop the fan. The fan won't run continuously iirc.
I believe all my main power rails are present and within the specified range. I used this , along with other forum posts to guide me on what i should be measuring and how much voltage i should expect. I assume with the chart i linked, if any rail is missing, rails that occur later in the list would not be present, right? Maybe this is where my ignorance sets in... I haven't recorded any of the voltage from the power rails that i checked, as i didn't notice anything wrong with them.
I did check my CPU core voltage, PPVCC_S0_CPU, and I think i am getting a high voltage. I'm getting .8 v and its not stabilizing to .6-.7v, which i had read is the proper voltage. This voltage will return to 0 with the amp cycle of the board. It seems to come on and off when current draw is at or about .3a. CPU is warm.
I read that these boards will not boot without a battery. I'm not sure if DFU mode is accessible without the battery installed. With the board on the bench,no battery, I don't measure any voltage at SoC_DFU_STATUS. I don't know how to get to this test point without installing the board. Maybe the battery is dead and it needs to be charged? With corrosion previously present at j6941, could this have damaged the battery? should I try a new one from Amazon to see if i can get it to boot?
This is where i'm stuck. Being a novice, I don't know the normal operation state of these boards and i find it difficult to find information of that.
To me, the board seems like it wants to boot. Maybe there is something wrong with my t2.
Apologizes if this was long-winded or confusing. Any help or guidance would be greatly appreciated.
