Salta al contenuto principale

iMac Black Screen & Loud Fans

iMac starts up with no chime. Also the fans start fine then after a minute or so go really fast. The screen also stays black.

The first two diagnostic LED light are lit. 3 & 4 stay off.

I can see no bulging or leaking capacitors.

Any ideas would be grateful.

Many thanks in advance,

Lewis.

Rispondi a questa domanda Anch'io ho questo problema

Questa è una buona domanda?

Punteggio -1
Aggiungi un commento

2 Risposte

Risposta Più Utile

Led 1 means that the computer is receiving a source of power. When this is on the computer will be plugged in. LED two goes on when the computer has constant power and tries to boot up. Now here is the problem that you are having, LED 3 isn't on which suggests a video related issue. LED 3 means that video signal is being generated. If this LED isn't on then the computers graphics card has failed. This means that you can do one of two things. One, you can try a video card reflow(google it), or two, you just need a new logic board. The only sure way to fix this is with a new logic board. Sometimes the reflows will only work temporarily. Unfortunately this is the only thing that you can do because that is the only problem related to not having LED 3 on.

Hope this Helps.

Questa risposta è stata utile?

Punteggio 2
Aggiungi un commento

I had similar problem - turns out one of the 2 SIMM (RAM) cards wasn't fully inserted. When I corrected this, started up normally.

Questa risposta è stata utile?

Punteggio 0
Aggiungi un commento

Aggiungi la tua risposta

Lewis sarà eternamente grato.
Visualizza Statistiche:

Ultime 24 Ore: 0

Ultimi 7 Giorni: 0

Ultimi 30 Giorni: 0

Tutti i Tempi: 4,138