820-3437 Fan speed, no chime, has Vcore

[Alan.L]

this board has been ultrasonic by the previous shop. NO History. Light goes green then orange on the MagSafe and No chime.

Doesn't do the usual 3x start, stop fan sequence. the fan is always going at full speed. CPU goes warm. CPUVcore at 1.7v

I've tried another BIOS from the same 3437 board.

No mouse activity on a USB PORT

PPBUS_G3H = 8.58
PM_S0_PGOOD = 3.4v
SYS_PWROK_R = 3.4v
ALL_SYS_PWRGD = 3.3v
PP3V42_G3H = 3.4v
SMC_DELAYE_PWRGD = 3.4

 

[JohnB8812]

How warm does the CPU get? Resistance to ground on VCore? Resistance to ground on pin 2 of PPBUS_G3H fuse?

 

[Alan.L]

quite warm, doesn't burn my finger.

Resistance to ground on VCore = 81.0ohm. - (on a known working board is same.)
F7140 pin2: Resistance to ground is 2.711M ohm - (on a known working board is similar .)

 

[2informaticos]

Check U1950 area.
Do you get correct signals at pins 3 & 7?

 

[Alan.L]

SYS_PWROK_R = 3.4v
PM_S0_PGOOD = 3.4v



this is trash probably

 

[larossmann]

This is done for.