Tuesday, March 01, 2016

Apple macbook pro 17 – Resetting – Troubleshooting shutdown problems - Laptop repair and service

Category: Laptop Repair and Service 

Contents of this article 

  • Resetting the parameters of macbook
  • Troubleshooting macbook 
  • Hardware relate problems 


Apple macbook pro 17

Resetting the System Management Controller (SMC)
To reset power management via the SMC chip:
1. If the computer is on, turn it off by choosing Shutdown from the Apple  menu.
2. Connect the power adapter to the computer and to a working power source.
3. Important: Use the keys on the left side of the keyboard. On the built-in keyboard, press Shift-Control-Option along with the power button once.
Note: When the LED on the MagSafe connector is orange, resetting the SMC will change it
to green for a few seconds, indicating that SMC was correctly reset.
4. Wait 5 seconds and press the power button to restart the computer. Note: If bottom case is removed, you may alternately reset the SMC by disconnecting the power adapter and the main battery, and holding the power button down for five seconds.
Resetting the Parameter RAM (PRAM)
To reset PRAM,
1. If the computer is on, turn it off.
2. Locate the following keys on the keyboard: Command, Option, P, and R. You will need to hold these keys down simultaneously in Step 4.
Note: If the keyboard does not have an Option key, use the Alt key instead.
3. Turn on the computer.
4. Press and hold the Command-Option-P-R keys.
Important: You must press this key combination before the gray screen appears.
5. Hold the keys down until the computer restarts and you hear the startup sound for the second time.
6. Release the keys.
Starting Up in Safe Mode
A Safe Boot is a special way to start Mac OS X when troubleshooting. To start up into Safe Mode
(Safe Boot),
1. Make sure the computer is shut down.
2. Press the power button.
3. Immediately after you hear the startup tone, press and hold the Shift key.
Note: The Shift key should be held as soon as possible after the startup tone but not before.
4. Release the Shift key when you see the screen with the gray Apple and progress indicator (looks like a spinning gear). During startup, ”Safe Boot” appears on the Mac OS X startup screen. To leave Safe Mode, restart the computer normally, without holding down any keys during startup.
Troubleshooting Shutdown Issues
Before troubleshooting shutdown issues, always do the following:
# Run the available Apple diagnostics to check for cause of previous shutdown(s). Running ASD also helps isolate any abnormal value reading from a thermal, voltage, or current sensor or from a fan speed meter.
# Collect all available information from the user on shutdown details: periodicity, power state
when issue happens, running applications, running time before shutdown.
User-related shutdowns
A computer shutdown may be caused by user operation. Shutting down the computer (by selecting the Shut Down menu, by pressing the power button for at least 4 seconds, or by programming a timed shutdown in the Energy Saver preferences) should not be considered as a failure unless the power button or the magnetic sleep sensors are found to be defective.
Suggested steps for troubleshooting:
# Reset SMC.
# Check Energy Saver preferences settings.
# Test top case button and magnetic sleep sensor operation and secure connection to logic board.
Activity-related system shutdowns
These shutdowns are linked to system settings, devices drivers, applications, or operating system freezes.
# System could not finish the standard shutdown process and had to force shutdown.
# An installed watchdog detected that an application did not respond within the specified time. (This watchdog can be enabled in Mac OS X Server Energy Saver preferences.)
Suggested steps for troubleshooting:
# Check the system logs and activity monitor utility for clues on the freezing process.
# Check for available software and firmware updates for installed device drivers, applications, or operating system.
# Start the system from a known-good and up-to-date bootable drive for issue reproduction.
Power-related system shutdowns
These shutdowns are due to power management, poor connections or defective power sources.
# External or battery power source was removed.
# Battery went empty while computer was on.
# Battery went empty while computer was asleep.
Suggested steps for troubleshooting:
# Reset SMC.
# Check that AC cable, AC adapter and battery connections are secure to logic board.
# Verify battery and power adapter sources using the Battery and Adapter test utility.
Hardware-related system shutdown
These shutdowns are due to temperature, voltage, current, fan speed or other hardware-related sensor values going out of range.
# One of the temperature sensors reached a specified temperature limit.
# One of the voltage sensors reached a specified voltage limit.
# One of the current sensors reached a specified current limit.
Suggested steps for troubleshooting:
# Check all sensors connections and values using Apple Service Diagnostics and other available Apple Service utilities.
# Confirm correct Apple-branded battery and power adapter are installed.
# Check for abnormal battery temperature.
# Check fan(s) operation.
# Confirm cleanliness of heatsink fins and air flows.
# Confirm heatsink is correctly seated on logic board and thermal material is present.