Apple MD094LL/A manual Symptoms Quick Check Intermittent Shutdown, Powers off during startup

Quick Check

Symptoms		Quick Check
Intermittent Shutdown		1.	Make sure that power cord is securely attached
•	Powers off during startup.		to the back of computer, and is not hindered by a
• Powers off during desktop use.			desk or other furniture.
•	Computer restarts	2.	Plug computer directly into an AC outlet to test if
	spontaneously.		a surge protector or UPS is causing issue.
• Powers off when waking from		3.	Open System Preferences > Energy Saver >
	sleep.		Schedule and make sure that a “Shut Down”
			event is not scheduled.
		4.	Isolate OS by starting up from original install
			media for this computer, from a same-model
			computer in Target Disk Mode, or from a
			compatible known-good OS on an external drive.
			Both AirPort and Bluetooth services are available
			when booted from the Install disk.
		5.	Reset SMC and PRAM to clear any stored,
			corrupted information.
		6.	Start up in Safe Mode by holding shift key down
			during startup to load only required kernel
			extensions and disable all startup and login
			items. See kBase #HT1564: Mac OS X: What is
			Safe Boot, Safe Mode?

2010-09-09 iMac (27-inch, Mid 2010) Symptom Charts — Startup and Power  41