Acer Aspire 7000 Series, Service Manual

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Chapter 4 78
T
Numeric keypad
T
External keyboard
If any of these devices do not function, reconnect the cable and repeat the anterior procedures.
Memory Check
Follow the procedures below to correct the memory errors.
1.
Boot from the diagnostic diskette and start the diagnostic programs.
2.
Go to the diagnostic memory in the test items.
3.
Press F2 in the test items.
4.
Follow the instructions in the message window.
NOTE: Make sure that the DIMM is correctly inserted into the connector. A wrong connection will cause
errors.
Power System Check
To verify the symptoms, power on the computer by using the following power sources separately.
1.
Remove the battery pack.
2.
Connect the power adaptor and check the power supply.
3.
Disconnect the power adaptor and install the battery pack, then check the power supply.
If you think there is a power supply problem, please go to “Check the Power Adaptor” and “Check
the Battery Pack” in this chapter.
Check the Power Adaptor
Unplug the power adaptor cable from the computer and measure the output voltage at the plug of
the power adaptor cable. See the illustration and follow the procedures below.
1.
If the voltage is not correct, replace the power adaptor.
2.
If the voltage is within the range:
(1)
Replace the system board.
(2)
If the problem is still not resolved, see “Undetermined Problems”.
(3)
If the voltage is not correct, go to the next step.
NOTE: An audible noise from the power adaptor does not always indicate a defect.
3.
If the power-on indicator does not light up, check the power cord of the power adaptor for
continuity and correct installation.
4.
If the operational charge does not work, see “Check the Battery Pack”.
pin 1: +19V to +20.5V
pin 2: 0V, ground