Apple Cinema Display 20"

[trwilson70]

Picked this up last month without a power supply. After getting the correct Apple power supply, 24.5v, unit would not turn on. After I disassembled, was able to verify that it is getting power. Caps appear to be United Chemicon KZH - using ESR meter, they measure OK. I have 24.6v across 5 caps at bottom, nothing across the two @ mid photo. Sometimes the LED, circled in yellow will come on when energized, sometimes not. Regulator in red is 1117-3.3, but am not getting a reading. Switcher in red, from top down reads, 5.03,24.6,14.91,0,0,5.01,6.31 volts. Lots of small SMD stuff!! Need help to get power. In testing small transistors - E to C should be open?

[styxbound]

Re: Apple Cinema Display 20"

I've had one of those things for quite some time now with no power supply. The supplies I've found are super high priced, and I saw something which said you had to have a G4 or G5 Mac to use it. What kind of info do you have about all that?

[trwilson70]

Re: Apple Cinema Display 20"

I've had one of those things for quite some time now with no power supply. The supplies I've found are super high priced, and I saw something which said you had to have a G4 or G5 Mac to use it. What kind of info do you have about all that?

Yes, the power supplies are too expensive - $70 and up for a 24.5 volt with their proprietary connector. I found one out of China on ebay - $36 delivered but had to wait about 3 weeks. Then when it wouldn't power on - I had to open and make sure the power supply was good. Not being familiar with apple products I wondered whether they needed a computer hooked up in order to operate and whether they would hook up to a PC - appears to have the same DVI connection. Apple is completely new to me - any help appreciated - just trying to recoup my investment at this point. Thanks

[styxbound]

Re: Apple Cinema Display 20"

Well, the good part about mine is that it was free. The bad part is that it makes me sick just sitting here when I so much want to use it. Keep hoping I'll somehow acquire the necessary Mac to use it.

P.S. From what I could find on Google this thing cost $1100 or more originally.

[Deet]

Re: Apple Cinema Display 20"

Just wondering trwilson70 have you had any luck with you cinema display I have two of them a 20 and a 23 inch not working I can get them to come on most of the time buy cycling the power on and off a couple of times I have checked the 23 inchs caps and reg. and they seem ok.

[johnz]

Re: Apple Cinema Display 20"

got this info from another site....check the VR3 3.3VDC REGULATOR center pin to make sure it is putting out 3.3v, bad one will put out about 4vdc

[budm]

Re: Apple Cinema Display 20"

http://s807.photobucket.com/albums/y...ema%20Display/

http://s807.photobucket.com/albums/y...y%2023%20inch/

[johnz]

Re: Apple Cinema Display 20"

budm which 3.3VDC REGULATOR would you recomend? Is this one ok http://www.digikey.com/product-detai...483318?cur=USD ?

[shovenose]

Re: Apple Cinema Display 20"

Well, it won't turn on without being attached to a computer with DVI that's powered on.

[budm]

Re: Apple Cinema Display 20"

3.3v 1A Fixed, that should be fine.
Does the output read close to 4vdc?

[johnz]

Re: Apple Cinema Display 20"

Im still doing my homework on how to take it apart...and reading up on it..before i start..

[johnz]

Re: Apple Cinema Display 20"

ok i got it out...middle pin output reads 2.7vdc??

[budm]

Re: Apple Cinema Display 20"

That is bad, when it failed, it can be higher or lower than what it should be.

[johnz]

Re: Apple Cinema Display 20"

Thank you...fixing to order the part...and see how it goes..

[johnz]

Re: Apple Cinema Display 20"

YES!!!!! IT worked..!!!!! Thankyou Budm for your help!!!

[budm]

Re: Apple Cinema Display 20"

Great!
Most people on youtube will tell you to mask off the sensing pin on the power connector or buy new power supply, but if the regulator puts out 4v or higher, then sooner or later the main board may be damaged.