820 3437 then spin , then stop .

[funtotos]

Hi all

I've got a 820-3437. When I connect the magsafe the fan spins then stops, then spins then stops but no start.
green light on charger :

pp5v_s5 ok
PP3V3_S5 ok
PPVRTC_G3H ok

no P5VS4RS3_EN
no PM_SLP_S5_L
no SMC_S4_WAKESRC_EN
no S4_PWR_EN
no PM_SLP_S4_L

no short

any ideas ?

 

[2informaticos]

Toooooooooooooo many "no" there.
Imposible, if the fan spins...
So check if all coils get pulse at least.
ALL_SYS_PWRGD pulse too?

Catch the voltages when the fan spins, of course.

 

[funtotos]

when the fan spins
ALL_SYS_PWRGD : 3.35v 2 second

I don't know the history

thks

 

[2informaticos]

Any pulse at CPU coils too?
Check for pulses at U1950, pins 7 & 3.

 

[funtotos]

u1950 pin 7 and 3 = 3.43v (fan spin)

When i connect the magsafe the first time , no boot (green light and orange )
When i connect the second time , the fan turns then stop (green light and orange )

 

[Paul Daniels]

Check that you're getting PPRTC_G3H at the rest of the board, not just on C1910