3 Beeps When My MacBook Pro Is Turned On
Customer Provided Symptom: “When I turn on my laptop I get a black screen and a 3 loud beeps that indicate there is no ram installed. Of course there are 2 1gb ram cards installed. I suspect that the problem is not with the cards but the board that reads them, but I have no way to tell?”
Mac Type: 15-inch MacBook Pro
Likely Cause: 3 beeps with a black screen when you power on a Mac is a memory error message. This can be caused by one of 4 things: 1. A problem with one or more RAM chips. 2. An issue with the logic board concerning the RAM connections. 3. Loose RAM chips. 4. No RAM chips are installed.
Solutions: If your comfortable working with RAM and have a static free station, then the first step in the above situation is to remove and re-seat (reinstall) the RAM chips and reset the PRAM.
Second step would be to isolate the RAM. If you have two sticks of RAM, try removing one and test, then swap the location of that chip and test. Repeat the steps with the other stick of RAM. This can help determine if one of the RAM sticks has failed or if one of the RAM slots is having an issue.
Third step would be to remove all RAM and try other compatible RAM (if you access to some.)
It’s possible that if all of the above doesn’t work or identify the problem, that the issue may be with the logic board itself. MyService can diagnose this issue and provide options for repair.