(347) 552-2258 [email protected]

820-3787: One Beep Code

M

macRepairAmb

Member
Hello

Have a 820-3787 with one beep code for no ram installed. Are there other issues that could cause this failure and not the ram.

Customer claims it originally had issues with the track pad, so he/she replaced it with another trackpad which is when the beep started. They Reinstalled the original trackpad with the same beep code. I hooked up the medusa and it says the VSS PRAM block not found. Could this be the issue, that its just a corrupted bios chip?

FYI: fan does spin.
 
M

macRepairAmb

Member
It fails every time I try to do it on the logic board. I?ve ordered the adapter for the Medusa so that I can solder the chip on it and do it off the logic board.
 
M

macRepairAmb

Member
Ok finally received the board, pulled the efi chip, and then cleaned the ME region with MedUSA. Still having the same single beep code.
 
2informaticos

2informaticos

Administrator
Staff member
Disconnect RIO board and other perypherals.
Keep only LCD connected.
Try even without LCD, external video through Thunderbolt adapter.
Investigate PCH SMBUS...
 
M

macRepairAmb

Member
PCH SMBUS signals matched with another known good board.

Apart from no data being transmitted from and to the RAM's, the only other measurements i found that was different was the MEM_B_CLK which is reading at 580mv while all the other boards i tested were measuring at 640mv. Source for this signal is from the cpu.
 
2informaticos

2informaticos

Administrator
Staff member
I had one last month with the same symptom.
It happened after LCD changing.
God knows what they f***d on the board.
 
You must log in or register to reply here.
Top