820-3209 - 3 Beeps Issue

mccafe

Member
Hello,

C7553 was shorted (PPBUS_S5_HS_COMPUTING_ISNS). Replaced and now got fan spin, but getting 3 beeps indicating RAM issue?

Battery is connected and it runs off battery just fine.

PPBUS_G3H = 8.4 volts
PPDDR_S3_REG = 1.359 (low?)
PPVCORE_S0_CPU = 1.1 volts
PPCPUVCCIO_S0_REG = 1.08 volts
PP0V75_S3_MEM_VREFDQ_A = 0.67 volts

PP3V3_S0 = 3.3 volts

How should I begin troubleshooting this?

Thanks!
 
Last edited:

mccafe

Member
EDIT: I fixed it by reflowing all the RAM chips. I figured I probably used too high of a temperature for removing the shorted cap on the other side of the board.
 

2informaticos

Administrator
Staff member
STOP to use hot air to change the caps!
Add 138 degrees alloy, or solder paste, on the terminals first.
Then is very easy to remove it with the solder iron.

58 degrees alloy is better.
I did it this way, before getting the JBC tweezer.
 

mccafe

Member
Thank you for the tip! I will get some ordered.

As for your tweezers, which model do you recommend? I want to look into this.
 
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