Likewise this could occur as it contracts, or if it gets dried out. If the former is true, then when it warms up it could potentially fail by cracking, or even pulling away from the surface it is adhered to. My thinking is that the paste contracts and/or dries out when exposed to extremely cold temperature. That and the fact that the MacBook Air is so thin, and there is no real thermal insulator between the case and the logic board. Although this area of the pickup truck should be insulated (you would think, as this console is specifically marketed pitching it as a place to store your notebook computer), it seems to not be so. Specifically, it has been left out in the center console of my 2007 Tundra when it has been very cold (10º F to 20º F). Each time I have run into the 3 beep scenario, it has occurred after the MacBook Air has been exposed to extremes in temperature.

Please let me explain, as I do not think there is anything inherently wrong with this model. Having now had to do this repair twice, I am beginning to suspect that environmental conditions (temperature, ambient humidity) are directly affecting thermal paste on the Macbook Air (as least the Rev C). WARNING: You should do this ONLY you are an experienced repair person, and only if your computer is already out of warranty.įYI: I've been building, repairing and modding computers since 1987. Therefore, if you have recently had a MacBook Air exhibit the 3 beep boot failure, strongly consider checking your thermal paste. Rebooted and NO 3 beeps! Once again, my MacBook Air appears to be working perfectly. I then removed the heatsink I found the thermal paste dried and hardened! I carefully removed all of the old paste and then applied new high quality thermal paste. Nothing else appeared burned, fractured, loose or disconnected.

When I got down to the logic board, I inspected the 8 visible 1 gigabit chips visible. Made no sense that DRAM of any sort would fail after 15 months. On a hunch, as I have noticed my MacBook Air has overheated in the past, I opened mine up to check the THERMAL PASTE. NEWS FLASH for MacBook Air users with 3 Beeps at startup!!! I'm no professional here but I would prolly try this.

Macbook pro 3 beeps startup