Shutting down problem.

Start > Control Panel > Power Options> Choose what the Power buttons do>When I press the power button

Ensure this is set to Shut down for both Battery and Plugged in. Save Changes

Then goto Device Manager>Network Adapters>Double click on your Wireless Adapter>Power Management

Ensure Allow this Device to wake computer is unticked

and do same for your Ethernet Controller

Hi August16,

I would suggest you to reinstall the video card driver on the system for issue resolution.

Please enter your service tag # on the link below, select the OS, then download the video card driver from Video section onto the system, and install it.

http://dell.to/ZaQuel

In addition, I would suggest that you run the diagnostics on the computer by following the steps mentioned below and check if there is any issue with the hardware on your system.

1. Turn on or restart the computer.
2. Immediately at the Dell logo screen, starting tapping the key once a second until the One Time Boot menu appears (if the computer boots to Windows turn the computer off and try again).
3. At the One Time Boot menu, press the arrow key to highlight Diagnostics, PSA+ or Enter ePSA, then press to begin the hardware Diagnostics.
4. Write down any error codes listed. Reply to us with the error codes.

Hi Paul, I have restarted my laptop on your  suggestion to choose the power button and save it  even I have done with the wireless adapter but on the device manager it does not show and Ethernet controller . It still shut down entirely the same it still restarts on its own ending up showing to  save mode or start manually. Any suggestion regards about this issue. Thanks!

Yes, I have run the diagnostics Error Code 2000-0142 I would appreciate what this means. Thanks!

Error code 2000-0142 means the HDD is faulty and requires replacement.

It's likely the system is out of warranty so you will need to source the drive yourself. 2.5" SATA HDD are relatively cheap and easy to fit

ftp://ftp.dell.com/Manuals/all-products/esuprt_laptop/esuprt_inspiron_laptop/inspiron-1525_service%20manual_en-us.pdf 

The only thing a failing drive is good for is the bin.

Back up your personal / important data ASAP.

Failing HDD can cause shutdowns so ignore my previous advice regarding the Power Settings.

However, It is also possible that the HDD needs re-seating. Re-seat the drive and re-run Dell Diagnostics. If the error code reappears then the drive needs replacing.

Service Manual (Guide to HDD removal / re-installation)

ftp://ftp.dell.com/Manuals/all-products/esuprt_laptop/esuprt_inspiron_laptop/inspiron-1525_service%20manual_en-us.pdf

Regarding Ethernet Controller..even though you say the controller is not visible in Device Manager..Please check in Device Manager...look under Network Adapters and check for Marvell 88E80XX 10/100 Ethernet Controller entry.

If you are having problems with the Ethernet port go into the BIOS Setup Menu which is F2 at boot when you see the Dell logo and disable it in the Setup :Menu and see if it makes a difference.

Ok, maybe I have to change my HDD and have it as a back up. I am  just thinking, would it be also the cause of shutting down issue and  Ethernet port cannot be detected? Advise please. Thanks!

Hi August16,

As suggested by Paul the error indicates that the hard drive is faulty. Please consider backing up the data and replace the hard drive on your system.

Thanks for the advises and I really appreciate it.  I will replace my HDD for now and I will send an update as soon as possible.