Skip to main content

Model A1174 with 2 GHz Core Duo or Model A1207 with 2.16 or 2.33 GHz Core 2 Duo

212 Questions View all
Question Closed

Only 2 LED's working! Please help, I need this computer for school!

Apple iMac "Core 2 Duo" 2.16 20-Inch Specs

Identifiers: Late 2006 - MA589LL - iMac5,1 - A1207 - 2118

Hi, I have a white IMac, last three digits of its serial number is VUW!

If I press the power button, there is no chime! The screen is black and it does not start up! On further investigation, I discovered that the fan is running and LED 1 and LED 2 are on!

I had a previous problem, caused by a faulty power surge protector where only one LED worked, I replaced the power supply, that fixed the computer! Alas it seems that the wall socket is faulty, and it died again! I won't make that mistake again!

So this time only 2 LED's working, fan working and black screen and no chime?

Can anyone help, I really need this fixed before school starts!

Thanks so much!

Christine

Answer this question I have this problem too

Is this a good question?

Score 0
Add a comment

1 Answer

Most Helpful Answer

LED 1 indicates that trickle voltage from the power supply has been detected. This LED will be ON when the computer is turned off and your power supply is working correctly.

LED 2 indicates that the main logic board has detected proper power from the power supply when the computer is turned on. This LED will be ON when the computer is turned on and the power supply is working correctly.

LED 3 indicates that the computer and the LCD display are communicating. This LED will be ON when the computer is turned on and video signal is being generated.

LED 4 lights only if the computer detects an over-temperature condition. This LED will be OFF when the computer is turned on and running at the correct temperature.

Inspect the 24 capacitors for bulging and/or corrosion. There was also a GPU problem on this one. The solder joint failed as the machine heated up and this can sometimes be repaired with a solder reflow. Take a look and let us know what you find. The LED's indicate a bad GPU (video card). This machine also has integrated video. The first thing I would check is the RAM to see that they are a matched pair and seated properly: http://support.apple.com/kb/ht3246

Was this answer helpful?

Score 2

1 Comment:

I don't understand Mayer what you write about LED 4. I understood that LED 4 should light up on startup but then shut off again? My LED 4 never lights up. I have a black LCD but working external monitor and the internal is never detected.

by

Add a comment
View Statistics:

Past 24 Hours: 0

Past 7 Days: 0

Past 30 Days: 0

All Time: 157