Fan is on all the time
Hello,
I have read similar threads here but not exactly this one. I had my MacBook Pro 2.4Ghz for motherboard repair. When I got it back the fan is an all the time, even when the MB is cold. I have done the SMC reset, PRAM reset etc. with no help. I ran iStat Pro and it says that left fan is 0 rpm and right fan is 2000 rpm. So I opened up the MacBook and I see that the left fan is the one really blowing away while the right fan is moving much quieter. The CPU load is low and the temps are low. I read about someone suggesting a sensor might be disconnected and that could be the reason iStat does not see a left fan even though it is blowing like crazy. Does anyone have a link to where I can check if this sensor is not correctly in place after the repair? Just to make sure I am testing with 85W power.
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NOW SOLVED!
Here is what I did. I opened the MacBook Pro and removed the left fan cable. Careful, careful, the correct way to remove these contacts is to gently pry with a spudger (Spudger) or similar and gently pull upwards. Look carefully for the text "Push" on top of the contact. I know because I have done my mistakes on these cables through the years :-(
I inspected the cable and made sure they were well seated into the contact. Put the fan cable back in place and now both fans are visible in iStat. So it must have been one of the 4 cables to the contact that has come loose when the fan was put back. Horray! MacBook Pro 2.4Ghz with 256MB vram ATI8600M (not bad really!) working for me again :-)
Is this a good question?
4 Comments
I had this MBP repaired in China so it is far to send it. Just thought I could make a shot. When I run the ASD DVD it starts up and then the screen goes black! So I can hardly see what is on the screen and can therefore not do anything. The screen never goes black in normal use.
by asle
Interesting, fan on high plus blank screen usually means it's overheating, or some other low-level basic issue. To rule out a screen issue try connecting to external video -- if that works fine while the laptop screen is blank, you know it's a screen-related issue. If you shine a flashlight on the display from the back through the Apple symbol, can you see any image (meaning the backlight is off/dead), or is it completely blank?
by rdklinc
But again, fan on high + screen blanking probably means something basic with the motherboard swap went wrong, rather than a bad component. I'd open it up and check all your connections to see if something is loose, etc. I would also test the memory.
by rdklinc
I connected an external screen while running ASD and it was blue. I see the normal ASD screen picture but it is too dark to see enough to know where the mouse is. So just the backlight is off. Strange that the screen is normal when I boot from the hard drive ... I Wonder why iStat reads 0rpm for the left fan, the one that is blowing crazy. Seems some sensor is not in place(?) Anyone know if a sensor goes to the left fan and where?
by asle