Ambient Light Sensor problem

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Hardly more than 90 days old, our MacBook 2.4 was already featured here as it has already caused me some trouble. Not a good thing I have to talk about it again: Yesterday it stated to make fan noise when idle, and the display backlight was changing for no apparent reason. After several unsuccessful attempts, I've found this article about resetting SMC as somewhere else I was suggested it might help.

Unfortunately though the SMC reset did help with the fan noise it left my system with no ambient light sensor. Whether it was related or not I do not know, but now I cannot use F5/F6 to change the keyboard backlit which remains off. I get a forbidden sign as if the ambient light was very high so as not to require any keyboard backlit. Unfortunately this seems not to be the case in my dark room and it still refuses to allow me to switch the backlit on.

The next exercise on the list was to perform a PRAM reset, that did not fix anything either. And, according to Apple support, the next step is to go to the technical service.

At least I've found a nice application that allows me to select the desired level of keyboard backlit: Lab Tick.

I'm still uncertain on this issue as it might be a firmware problem or a hardware problem. At any rate I'm stopping to recommend Apple as a trouble-free brand (two issues in three months with a system is not good).

Update: MacBook was serviced by Apple and the whole display replaced (apparently the change the whole screen to fix this problem).

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