Where Might the Fault Lie in an iMac That Will Not Power On?
In the iMac the power supply unit (PSU) is located inside the case, in the same compartment as the logic board. Power fluctuations, sudden outages and worn capacitors are the most frequent causes of failure of this unit. However, the complaint “it does not turn on” does not by itself point to the power supply; the supply cable, the power button cable, the standby line on the logic board or the backlight produce the same result as well. The crucial distinction is this: if the device is silent and there is no light at all, the power side is examined; if the fan is spinning but no image appears, the display side is examined.
Differentiation According to Symptoms
- No sound and no light at all: The power supply, the supply cable or the standby line. This is the most frequent scenario.
- The fan spins, the screen is black: There is power; the problem lies in the backlight, the panel or on the graphics side.
- Powers on, then shuts down after a few seconds: A power regulator fault or overheating protection.
- The fans spin at full speed, it will not turn on: A temperature sensor connection or power line problem.
- It did not switch on after a power cut: A classic power supply capacitor fault.
- Sometimes it starts up, sometimes it does not: Cold solder joint or socket contact; the hardest type to diagnose.
Our Diagnostic Process
1. Ücretsiz Ön Kontrol
Şikâyetinizi sizinle birlikte dinler, sorunun nereden kaynaklanabileceğini ilk görüşmede konuşuruz. Basit bir sorunsa boşuna cihaz açmayız.
2. Arızanın Kaynağı
Sorunun güç ünitesinde mi, anakartta mı yoksa başka bir parçada mı olduğu atölyemizde netleştirilir. Tahmin üzerinden parça değiştirmeyiz.
3. Açık Rapor ve Onay
Arızanın ne olduğu, onarım seçenekleri, süre ve fiyat size açıkça bildirilir. Onayınız olmadan hiçbir işleme başlanmaz.
4. Repair or Replacement
Onarılabilecek arızalarda ünite onarılır; hasar genişse güç kaynağı değişir. Hangisinin uygun olduğunu size gerekçesiyle anlatırız.
Preventive Advice
In places where power fluctuations occur frequently, we recommend that you power the iMac not directly from the socket but through an uninterruptible power supply with a voltage regulator. This appreciably extends the service life of both the power supply and the motherboard.
At our service centre
Free Diagnosis
We take measurements to tell you whether the fault lies in the power supply or elsewhere.
Repair Priority
If the problem can be resolved at capacitor level, we do not replace the unit.
Measurement Under Load
The power outputs are tested under real load, not when idle.
Stability Test
Before handover the device is left switched on for a long period and monitored.