Contribution d'origine par : rwalmond ,
Have you even tried the simple PRAM (Parameter Random Access Memory) and SMC (System Management Controller) reset? Even though this is a complicated issue, it works most of the time for random software glitches. Shut down your Macbook first. Then plug in the cable and wait for 10 minutes to ensure there is some power running through your Macbook. SMC reset: Hold down the keys Shift, Control, Option and Power at the same time. Wait until you see that the cable LED colour changes, or just wait 10 seconds. PRAM reset: Press and hold the power button and then press and hold keys Command, Option, P, R. Hold those keys down until your Macbook reboots again. Then just let it boot normally.