Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

[XxMicroSoldering]

Hello Guys. Yesterday I was repairing a MacBook with no backlight. I noticed the resistor/diode RP802 is bad so I took it off. I also had a faulty motherboard that can't be repaired that had that resistor/diode on it (RP802). So it took the good RP802 off the faulty board. And when I had it on my tweezers it accidentally flew away. And now I don't know what to do. I 100% can't find it because of how small it is. Do you guys know any other diode/resistor that can work as the RP802


I'm a newbie to microsoldering and I'm still learning. All help is really appreciated



Regards

[mon2]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Hi.

1) it is an 0402 SMD size resistor that is very common and cheap to source.

2) See attached.

3) RP802 = 63k4 1% 0402 size resistor. The part does not have to be exactly this resistor value (but should be close) nor the 1% tolerance to function but best if you can source the same specification.

For example - ORDER SPARES - we usually purchase 50-100 pieces since they are so small and cheap:

(in random order)

https://www.digikey.com/en/products/...342GLF/3783457

https://www.digikey.com/en/products/...763K4L/5895464

https://www.digikey.com/en/products/...PF6342/4053213

There is also Mouser and Arrow electronics but the shipping may be higher. I know that for us in Canada - the shipping is a flat $8 from Digikey.

Your local Fry's store - may or may not have these as well so online is often more reliable.

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Hello Sir or ma’m

I don’t know how to thank you. But thank you so much for you’re reply means so much. As I said I’m a newbie to microsoldering and still learning when I was microsoldering a messed it up a bit. Look at the photos. Do you know how do fix this


Regards

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Here is the photo:

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Here is the photo:

As you can see I messed it up. Hope you can help me


Regards

[mon2]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Post a larger picture of this PCB area so we can determine where you are.

It will be best to practice soldering on a donor or scrap board from Ebay or similar before attempting this repair. This is a very high-density board with cell phone size parts and are very difficult to handle for even the experienced techs.

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Hello sir or ma'm

Here are the photos. As you can see there are in total 3 diodes / resistors missing do you know the name of them so that I can take them out of the donor board and install them in the good board. And how about the mess I made on the pcb how can I fix that


Regards

[mon2]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

RP801 = 80k6 = 80.6k resistor 0402 size 1% tolerance

CP800 = 1000pf capacitor 0201 size 10% tolerance; 16 volts or higher rating; X7R dielectric (this style defines the capacitance and how it will remain steady as the temp changes - too hot or too cold)

RP802 = (noted before) 63k4 = 63.4k resistor 0402 1% tolerance

Each of the above parts are with no polarity so they can be soldered in either direction.

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Thank you so much I understand. How can I fix that broken pcb then ? Or is that not broken ? Because I can't find the pads

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Cause that's my only concern

[XxMicroSoldering]

How to fix this (MacBook pro M1 2020 Motherboard

Hey Guys

I'm a newbie to microsoldering I messed up the board a little bit when replacing the backlight diodes and resistors does anybody know how to fix this coper part of the motherboard or is it good to go

[mon2]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

You have exposed some copper by removing of the topside solder mask. The solder mask is used to insulate the copper. It is not mandatory to have the solder mask so no issue there.

It is hard to see where the traces are on your board so you have some options:

1) using a meter, you can confirm if the traces on the PCB are properly connecting the components in this pic. Compare the connections with the schematic / boardview files for this logic board.

2) plan B: consider to remove some more solder mask so you can clearly view which traces are linked to this exposed ones in your pic. Then confirm the traces are ok with the meter (diode mode) testing again.

At a quick glance, do not believe you have any issues here other than some solder mask has been removed. Best to test the continuity before proceeding.

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Okay so I just have to put some solder on the pads and then place the resistor and diode in to place with hot air. You know the problem is I can't really find the pads and put some solder on it. I really hope you can help me

I see a message forwards

Regards

[mon2]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Post full details.

Which resistor?

Which diode?

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Hello

So to get this clear I have a donorboard of the same exact model MacBook. And you know I lost diodes/restistors on both the good board with no backlight and on the donor board.
RP801 = ?

CP800 = ?

RP802 = ?

To note on the donor board and good board with no backlight i lost all three but as you said these are just names and don't define voltage. Do you know wich other resistors and diode can act as RP801 / CP800 / RP802 on the donor board

Regards

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Post full details.

Which resistor?

Which diode?

Oh and how do you place back RP801/ RP802 / CP800 back in the good board

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Hi do you know how to fix the exposing copper parts

[adamski]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Hi, I would scrape all bad solder mask and then reapply liquid solder mask mask then cure it under uv. You should not leave so much copper exposed. I mean you can, but the repair will look bad. Also make sure you have no shorts to the ground before powering anything.

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Hi, I would scrape all bad solder mask and then reapply liquid solder mask mask then cure it under uv. You should not leave so much copper exposed. I mean you can, but the repair will look bad. Also make sure you have no shorts to the ground before powering anything.

Hi yes I understand. But the problem is how should I place back the diode / resistors when there is much exposed copper how to start?? Whole explanation

[XxMicroSoldering]

Re: Lost Diode/Resistor RP802 MacBook Pro 2020 A2338 HELP

Hi, I would scrape all bad solder mask and then reapply liquid solder mask mask then cure it under uv. You should not leave so much copper exposed. I mean you can, but the repair will look bad. Also make sure you have no shorts to the ground before powering anything.

Hi do you know it?