ZBook 15 (LA-9241P) Fan always on

[r ez a]

hello my friends
this laptop came with fan problem
as i measure FAN_PWM is always 0V and running full speed
but after windows totally boot up,FAN_PWM rise to fix 75%
tach signal working fine
flashing bios and ec doesn't help

what signals should i check ?

thanks

[kalilinux25]

Re: ZBook 15 (LA-9241P) Fan always on

hello my friends
this laptop came with fan problem
as i measure FAN_PWM is always 0V and running full speed
but after windows totally boot up,FAN_PWM rise to fix 75%
tach signal working fine
flashing bios and ec doesn't help

what signals should i check ?

thanks

tried changing the fan?

[Sephir0th]

Re: ZBook 15 (LA-9241P) Fan always on

Check whether the +5V for the fan is shorted with the +5VALW rail. Internal shorted load-switches happens from time to time.