MacBook Pro 13" Mid 2009: Fan doesn't kick in

[andytran]

A week ago, my MBP's fan stopped working. My MBP doesn't have AppleCare so I bought a new fan and replaced it. The new fan has been working like a charm but then I notice that my new fan doesn't kick in when the temperature goes up. It always stays at the mininum speed (set by smcFanControl - 3000 rpm) even when the temperature reaches more than 90 degree Celsius, although I can force it to spin at 6200 rpm by using smcFanControl.

I tried to reset the SMC & PRAM and performed an extended Apple Hardware Test but found no error. Please help! Is it possibly a software-related problem?

Additional info:

MacBook Pro 13" Mid 2009
Mac OS X 10.6.7
smcFanControl 2.2.2 (Default - 3000 rpm, Higher RPM - 6200 rpm)

 

[gorskiegangsta]

this is because when you use smcFanControl you have to adjust your fan speed manually. turn the program off and the OS will take care of fan management.

 

[andytran]

this is because when you use smcFanControl you have to adjust your fan speed manually. turn the program off and the OS will take care of fan management.

Hey gorskiegangsta I think smcFanControl only sets the minimum fan speed. Mac OS handles the fan mangement so it should be kick in in a higher rpm rate when the computer is heated. Correct me if I'm wrong

 

[gorskiegangsta]

Hey gorskiegangsta I think smcFanControl only sets the minimum fan speed. Mac OS handles the fan mangement so it should be kick in in a higher rpm rate when the computer is heated. Correct me if I'm wrong

I think it is only true on "default" setting. I played a game the other day (with smcfancontrol on) and the laptop got really hot but the fans didn't kick in until the cpu reached 98c; that never happens when the program is not running. IDK though, maybe it's just one isolated case. The program does make me weary though, so I rarely use it.

 

[andytran]

I think it is only true on "default" setting. I played a game the other day (with smcfancontrol on) and the laptop got really hot but the fans didn't kick in until the cpu reached 98c; that never happens when the program is not running. IDK though, maybe it's just one isolated case. The program does make me weary though, so I rarely use it.

I tried to uninstall smcFanControl and all its plist files, reset the SMC, and reboot in Safe Mode. The fan speed was reset to 2000 rpm. This time the fan automatically, albeit slowly kicked in around 3400 rpm when the CPU's temp reached ~85 degree and stayed at that speed for minutes. I think there maybe a problem with thermal paste or sensors =/

 

[NickZac]

What were you doing when it hit 85? That is not an unusually high temp for the mid 2009 C2D's at all...even with relatively moderate load work. What did the speed max at?

 

[andytran]

What were you doing when it hit 85? That is not an unusually high temp for the mid 2009 C2D's at all...even with relatively moderate load work. What did the speed max at?

I was doing some HandBrake encoding. The speed stayed around 3400 rpm.