My iMac CPU fan runs on high all the time.
I have done the usual SMC. PRAM resets with no luck. I have tested the fan and the control circuit an I believe they operate OK. I think it may be the LCD temperature sensor that is at fault but would like to prove this before I buy another.
Any ideas how to do this? I will measure the resistances between all pins and post them in the hope someone can test their system and compare measurements.
It's a 4 wire device... is it the same as the Ambient sensor??
One last note, I booted the system w/out RAM and noted that the CPU fan runs at normal low speed. Re doing this with the LCD temp sensor disconnected the CPU fan runs on high....
My iMac CPU fan runs on high all the time.
I have done the usual SMC. PRAM resets with no luck. I have tested the fan and the control circuit an I believe they operate OK. I think it may be the LCD temperature sensor that is at fault but would like to prove this before I buy another.
Any ideas how to do this? I will measure the resistances between all pins and post them in the hope someone can test their system and compare measurements.
It's a 4 wire device... is it the same as the Ambient sensor??
One last note, I booted the system w/out RAM and noted that the CPU fan runs at normal low speed. Re doing this with the LCD temp sensor disconnected the CPU fan runs on high....
My iMac CPU fan runs on high all the time.
I have done the usual SMC. PRAM resets with no luck. I have tested the fan and the control circuit an I believe they operate OK. I think it may be the LCD temperature sensor that is at fault but would like to prove this before I buy another.
Any ideas how to do this? I will measure the resistances between all pins and post them in the hope someone can test their system and compare measurements.
It's a 4 wire device... is it the same as the Ambient sensor??
One last note, I booted the system w/out RAM and noted that the CPU fan runs at normal low speed. Re doing this with the LCD temp sensor disconnected the CPU fan runs on high....