Questions about iMacs Ambient Light Sensor

[Zwhaler]

I read on Apples website that the iMac has an ambient light sensor that automatcally adjusts the sleep light so, as Apple says "You and your iMac can catch some Z's" But I noticed that on mine it seems like it doesn't work. I put the iMac on sleep, left for more than an hour, with the room being absolutely pitch black, and returned to find the sleep light still at the brightness it was when I first put the iMac to sleep.

Is it a defect? I hope not, because this computer is perfect and I would hate to need to send it in.

 

[mad jew]

I don't think Apple will replace an iMac because the sleep light doesn't dim at night.

 

[mongoos150]

A replacement? For a defective ambient sleep light? AHAHAHAHAHAHA!!!!!

 

[Superdrive]

What happens when you turn the lights on in the room? You might be seeing it at the dim setting. I've also seen a keystroke around here that adjusts the dimming on the sleep lights (I used it on my PowerBook months back).

 

[RobTuck]

A replacement? For a defective ambient sleep light? AHAHAHAHAHAHA!!!!!

I dont see whats so amusing. The fact that the sleep light isnt working properly suggests a fault somewhere.

The sleep light on my PowerBook didnt work as it should when I first had it. I didnt think anything of it, until about a year later when I started having problems with it sleeping randomly, screen dimming or going black at odd moments. I had to have a new ALS fitted, and the hard disk was replaced.

 

[Zwhaler]

A replacement? For a defective ambient sleep light? AHAHAHAHAHAHA!!!!!

Ok, first of all, what I wrote was not what I meant. I just worded it wrong. I don't want to have to send in the computer because of it, because I have heard of people haveing problems when the computer returns from repair.

 

[Zwhaler]

What happens when you turn the lights on in the room? You might be seeing it at the dim setting. I've also seen a keystroke around here that adjusts the dimming on the sleep lights (I used it on my PowerBook months back).

When I turn the lights on it just keeps doing as it was doing before. So basically there is no dimming that ever occurs.

 

[mad jew]

It's probably something as simple as dirt covering the light sensor. I'm not sure where the sensor is exactly (I think it's beside the light), but I don't think it's anything to worry about. If you notice any quirky behaviour or performance drops then take it back and tell them about the light sensor, but otherwise I wouldn't worry.

 

[imacintel]

It's probably something as simple as dirt covering the light sensor. I'm not sure where the sensor is exactly (I think it's beside the light), but I don't think it's anything to worry about. If you notice any quirky behaviour or performance drops then take it back and tell them about the light sensor, but otherwise I wouldn't worry.

Actually, its located beside the RAM slots.If you look the where the speakers are there should be a hole with no screw. That would be your ALS


Edit: Wow. I outsmarted Mad Jew. Hear that everyone?!

 

[Shadow]

Wow. I outsmarted Mad Jew. Hear that everyone?!

My god! Mad Jew, are you feeling alright? Here, let me get you a towel...

 

[Zwhaler]

So do you suggest I just blw into it or something? Any way to clean it? I'll see if blowing on had any affect.

 

[mad jew]

Okay, okay, shuddup you guys.

Blow into it by all means. I'm not suggesting this is the problem, but it could be. I'd try to keep troubleshooting a problem like this to a minimum since it could end up doing ore harm than good.

 

[Zwhaler]

Ok I tried blowing on it, now if I cover the sensor will it think the room is black and will dim accordingly? Will that be a good test?

 

[Zwhaler]

Well, after blowing on it, I put the computer on sleep and covered the sensor. No luck. Is there any settings or preferences regarding the ALS?

 

[EricNau]

Make your room dark and wave a flashlight across the sensor (slowly), you should see a reaction.

EDIT: OK, nevermind. No, there aren't any preferences regarding the ALS.

 

[imacintel]

Well, after blowing on it, I put the computer on sleep and covered the sensor. No luck. Is there any settings or preferences regarding the ALS?

Not that I know of. But is it really this important to you? If you feel you need to, call Apple.

 

[Zwhaler]

Ok i'll try that. How long does the light take to adjust to the light in the room? Should I call Apple? This is really bugging me because this computer will be in my room as of tomorrow.

 

[Zwhaler]

Yes it got much brighter when I put the flashlight on it. But for some reason when I cover the sensor it stays just as it did when I wasn't covering the sensor. It is kind of ironic, because I couldn't care less how bright it can get, all I want it to do is to turn off. Any way to disable it, if I can't find a solution?

 

[jsw]

It's probably something as simple as dirt covering the light sensor.

Not to be an idiot (intentionally), but... wouldn't dirt on the sensor have the opposite effect - making it dim all of the time (because it would always think it was dark)?

I suspect a faulty component, and it's up to you do decide if it's worth taking it in for repair.

The other possibly is a horny firefly on the sensor, but that's not all that likely.

Edit: never mind - it apparently gets brighter with bright light. That's probably as dim as it gets, then.

 

[Zwhaler]

Are you sure? I mean, do you know for a fact that it turns off when the room is pitch black, or does it flash anyway, because I don't care so much if it is working, but I just want to know if it ever turns off in a black room. But either way, is there a function to disable it? That would be lovely
Strange I always seem to have problems nobody's ever heard of.

 

[mad jew]

Not to be an idiot (intentionally), but... wouldn't dirt on the sensor have the opposite effect - making it dim all of the time (because it would always think it was dark)?

True. I was thinking of something like sand which might have some sort of cool light prism effect though... Irrespective, it doesn't seem to be the issue here.

 

[skunk]

True. I was thinking of something like sand which

You're just obsessed with food. Admit it.

 

[mad jew]

Hey, I'm having a dinner party tonight. That's perfectly understandable.

 

[EricNau]

Yes it got much brighter when I put the flashlight on it. But for some reason when I cover the sensor it stays just as it did when I wasn't covering the sensor. It is kind of ironic, because I couldn't care less how bright it can get, all I want it to do is to turn off. Any way to disable it, if I can't find a solution?

First of all, the light does NOT turn off (I'm not sure if this was your understanding or not). It just dims in the dark.

The fact that the flashlight did make a difference proves that the sensor is working, although perhaps not properly.

Is your room fairly bright with the lights on? Try turning your room's light's on and off, alternating between pitch black and light. You should see a fairly significant response immediately from the sleep light.

 

[Unorthodox]

Yes it got much brighter when I put the flashlight on it. But for some reason when I cover the sensor it stays just as it did when I wasn't covering the sensor. It is kind of ironic, because I couldn't care less how bright it can get, all I want it to do is to turn off. Any way to disable it, if I can't find a solution?

Sure.
Open the case by loosing the screws on the bottom of the unit.
Carefully remove the back panel.
This is also a good opportunity to clean out any dust that might have gotten inside when you where puffing away at the light sensor.
Now remove the logic-board assembly by taking out the screws that are located somewhere.
Scan the lower section for the led indicator light.
When you find it, grab it with a pair of pliers and give it a hearty pull.
Keep pulling until it rips out.
Now reassemble the unit and enjoy!