Logicboard RAM Repair A2251

[underwaterpilot]

I am attempting to repair my wife's Macbook Pro (A2251). I know that the RAM is bad and I was initially just getting ready to remove and reball the BGA chips.

Upon initial inspection I realized that it looked like there were two resistors missing on the logic board (highlighted below).

I got the board schematics (attached) and it looks like there should be a resistor there. I am new to looking at these drawings and don't know whether these resistors are configuration dependent or if they are actually missing. In the drawing they are the R2391_3 and R_2391_4 resistors.

I am looking to see:

• Should these resistors actually be there?
• What kind of resistors are they? (Not clear to me based on the drawings.... I have dealt with electical drwaings but this format is new to me)

Any help is appreciated! Also attached applicable drawing pages. Zip file contains applicable drawings and .brd file

 

[f54da]

If you don't get a response here, you might also consider posting on louis rossman's forum (requires a small fee to sign up though, presumably to cut down on useless posts). The readers there are likely to be more familiar with the board-level schematics.