User:Girishmg/sandbox/random shutdown syndrome

Random Shutdown Syndrome refers to Apple MacBook shutting down without warning. Once this occurs you could expect this to happen several times in a single day. Sometimes you cannot start the system for several minutes. If you try to turn it on, it will switch off in few seconds. From the majority of the postings online its speculated that cause for this is the cable between the heat sensor and the CPU's heat sink. As per the posting at, the problem seems to be

''The heat sink expands during operation and gets into contact with the sensor cable and melts the cable’s isolation. This in turn causes a short circuit and, thus, the immediate shutdown of the MacBook. As the heat sink is cooling down, the heat sink contracts to the point that it looses its contact with the cable and breaks up the short circuit.''

Sometimes if the MacBook turns on immediately it will not turn on and one might have to wait for minutes to turn it on. However it would randomly shutdown after some time. The frequency will gradually increase.

Apple advises in its support page to contact AppleCare for service. One would eventually end up visiting a nearby Apple Store for fix. The fix involves a replacement of HeatSink with sponge and some change in the circuitry path. This would generally take an hour time for a Genius at Genius Bar.

Testing your MacBook for Random Shutdown Syndrome
One can test whether their MacBook suffers from RSS by making both the CPU occupied completely for several minutes. Create a program which just runs an infinite loop. Now run two instances of this program. The first instance shoots the utilization of first CPU to 100%. And the second instance shoots the utilization of second CPU to 100%. With both the CPU's occupied for several minutes the temperature would increase and expansion of heat sink and possible short circuit and thus, the immediate shutdown of the MacBook.

JAVA Program would look like this:

public class RandomShutdownSyndrome { 	public static void main(String[] args) { 		while(true) { 			System.out.println("RandomShutdownSyndrome"); } 	} }

Compile the code using javac RandomShutdownSyndrome.java. Then run the code twice by typing java RandomShutdownSyndrome & twice at the Terminal command prompt

Disclaimer
The above test is not a conclusive test to tell whether your MacBook has RSS or not. Also you agree to run above tests at your own risk and would not held anybody responsible for any damage or loss that you may incur by running above test.