Thanks for the information.  I would like more information on the REED switch.  Where is located, and do you know a place I can buy it from?

Thanks again

Hi Tony,

I too had the same problem on my Dell 9200. Unfortunately my warranty expired on the same day as the problem appeared, I being in India could not get dell paid support for 9200 as laptop was purchased from the US and was not yet launched in India. On chat with US support they too could not trace the problem .

The problem is very small and simple. Since your laptop is under warranty just ask Dell support to replace the REED switch. I had the same problem and on going thru the forums read that this could occur due to a faulty switch which is used to suspend the laptop when you close the lid. But unlike other dell models the 9200 has a Reed switch and not a mechanical one (which often gets spoiled). I replaced mine myself and now my laptop works just fine.  A third party switch cost me Indian Rs. 25/- thats about less then 50 Cents.

If you need more help let me know.  Like the location / working of the switch etc.

The Reed switch is an electro magentic switch. It looks like a glass tube bulb for length 16 mm. To know more about its working  you can visit http://www.eleinmec.com/article.asp?23 .

If you would like to confirm that the switch is faulty .. remove the Laptop battery and reinsert it and then start the laptop the display should come on this time ( this was one of the symptoms that I had apart from the ones you mentioned)

With context to our laptop the switch is located in the touchpad assembley. Which is attached to the palmrest.You can go thru the Dell service manual on how to open the palm rest and reach it.  If you look from the top it is located somewhere on the right side, next to the right click button of the touchpad. The magnet is located on the topside of the display assembly panel. You can located the exact position of the magnet by moving a metal object ( like a key) close to the top edge of the panel between the two hinges. The place where it attracts is the location of the magnet. You do not need to replace the magnet. ( The place where the magnet touchs the palm rest when the laptop's lid is closed is the location of the reed switch)

Removing and Replacing the switch by yourself will require ( sound knowledge of electronics and) soldering which will void your warranty. So let Dell do this for you. If they refuse to just replace the switch then have them change the entire touch pad assembly thus in turn replacing the switch.

I purchased the switch from an electronic shop in India. I'm sorry I will not be able to help you with where to purchase it in the US but you can try online or an electronic workshop selling switches and spares or ask dell for it.

let me know if all this helps and your are able to fix your problem. Best of luck.  

The reed switch is  a very delicate item of size 16mm and width 3 or 4 mm.Its placed in a glass tube to prevent damage to it.  In the inspiron 8600 Dell was using a mechanical switch which used to get stuck and this problem used to start. So when Dell upgraded their model they replaced the Mechanical switch with a reed switch thinking this would not get stuck like the mechanical one. Unfortunately I think the reed switch too is prone to failure.

If you went through the URL I had mentioned earlier you will understand the working of the switch. When the switch gets spoiled what happens is that the two Prongs remain stuck togather and do not seperate even if the magnet is moved out of the vicinity. So in turn the LCD screen remains in Suspend mode.

I don't know if 9100 has a reed switch or not but 9200 for sure has one. If you can't find a mechanical switch then it must have a reed switch. (to confirm try finding the magnet).