My nv7802u laptop will not charge. No lights. No heat/energy at all. The charger is fully functional but the laptop will not light up nor charge what do ever. What could cause this? It was not dropped or anything, but just one day decided it wasn't going to work. Help?

How long have you left battery on charger? It will take about 3 1/2 hrs to fully charge. t is probably not a good idea to leave the battery in the charger for long periods of time though, so once it is fully charged put it back in the drill. When fully charged the green led will turn solid. This link will have more info on charger and battery.
http://powertool.manualsonline.com/manuals/mfg/ryobi/130155001.html?p=2 C

Make certain you are charging with the radio OFF. If on, the radio will use a small amount of energy and the charger will not know the battery is fully charged. If you intend to leave it on the charger, ON as in standby, then the lights will always flash. I would put a timer on the wall adapter so the battery is not always being charged. A battery always being charged will not last long, likely get hot and may cause problems. These are light duty radios, not designed for 24 hour if even daily use.

When this happends, the three usual suspects are the charger, the charging port (where the charger plugs into the laptop), or the motherboard itself.
Now to see where the problem lies. These would be my first steps...

1> Is there a light on the charger, if so, does it light up? If it does have a light, and it lights up then we can leave the charger out of the equation. If it has a light and it does not light up, we can assume the charger is the culprit. If it does not have a light, you will need a voltage tester.
2> Is where you plug the charger into the laptop loose? Sometimes, the charging port on the laptop can become loose (separation or partial separation (also known as a short) from the motherboard and loose the connection to the laptop. This keeps the energy from reaching both the laptop and the battery to create a charge.
God luck!

How long is it charging until the light goes from flashing red (no charge) to yellow to finally green (full charge) ? If it's not at least 2 hours, sorry I don't have my Roomba papers available, so I'm guesstimating here, it's not getting a full charge. If you can put a voltmeter on the " fully charged" battery pack, that might tell you if the charger is the problem. Clean off the metal contacts where Roomba meets the two metal contacts on the charger. Also just because a battery pack or set is new doesn't mean it's functional. I had a new Apple battery for my laptop that didn't work when I replaced an older one.

Hi Suzanne! Follow these steps to check that your charger and battery are working properly.

1. Unplug the charger for at least 30 seconds.
2. Plug the charger back in. The blue light on the charger should flash once.

If the blue light flashes once this is an indication that the charger is still functioning properly. If the blue light does not flash, the charger will need to be replaced. Follow this link to order a replacement charger. LiNX Battery Charger

3. Place the battery in the vacuum and turn it on for 30 seconds. (even if it does not turn on or powers off)
4. Turn the vacuum off.
5. Remove the battery and place it in the charger.

If the light on the charger is solid blue this is an indication that the battery has been reset. Allow 3-4 hours for the battery to fully charge. The blue light will start to blink slowly to indicate the battery is fully charged.

If the light on the charger is flashing blue or there is no light at all this can mean that your battery needs to be replaced. Follow the link to order a replacement battery. LiNX Lithium Ion Battery

Hope this helps!

please see the commentary. God bless you

• 
  The majority of laptops will display a solid green, blue or purple battery light to indicate that the battery is fully charged. Most manufacturers indicate that a laptop is in the process of charging by displaying a solid or blinking green, orange, blue or purple light. If your battery indicator light is green, blue or purple, the battery is probably functional, regardless of whether the light is blinking. If the light is solid orange, the laptop is probably in the process of charging.
  
  

Battery Error Coneventions

• 
  Many battery manufacturers use rapidly blinking lights to indicate that a battery's charge level is low. In general, a laptop will rapidly blink orange or red when its charge drops below a certain level until the computer is plugged into a power outlet and charged. If your laptop's battery indicator continues to blink rapidly in orange or red or if it remains red even when it is plugged into the charger, it indicates a problem with your battery or the charger.
  
  

Read more: http://www.ehow.com/info_12183593_blinking-battery-light-laptop-mean-charger-not-charging.html#ixzz2fu5qhEWg

please read and execute the commentaries. God bless you
Charging Conventions

• 
  The majority of laptops will display a solid green, blue or purple battery light to indicate that the battery is fully charged. Most manufacturers indicate that a laptop is in the process of charging by displaying a solid or blinking green, orange, blue or purple light. If your battery indicator light is green, blue or purple, the battery is probably functional, regardless of whether the light is blinking. If the light is solid orange, the laptop is probably in the process of charging.
  
  

Battery Error Coneventions

• 
  Many battery manufacturers use rapidly blinking lights to indicate that a battery's charge level is low. In general, a laptop will rapidly blink orange or red when its charge drops below a certain level until the computer is plugged into a power outlet and charged. If your laptop's battery indicator continues to blink rapidly in orange or red or if it remains red even when it is plugged into the charger, it indicates a problem with your battery or the charger.
  
  

This is the procedure for solving consider replacing your battery problem. Start by running the command prompt with administrator privileges. This will give the full control over the command prompt. There are those commands that can only be executed when you are using the command prompt with administrator privileges. Change the destination path showing on the command prompt to be set to C:\ then type the command POWER -ENERGY( to change destination path to C:\, type CD\ ). This command will make the computer scan the battery status and after 60 seconds, a report will be generated and saved in C:\. Simply open the energy report and scroll to check the battery information. Look for the design capacity and the last full charge, note the difference in this figures.
For my laptop, these were the details
Battery Information
Battery ID: Hewlett-PackardPrimary
Manufacturer: Hewlett-Packard
Chemistry: LION
Design Capacity: 88800
Last Full Charge: 36467

To remove the message consider replacing battery fully charge your laptop battery then unplug the charger to use the laptop on battery power. Use it until the laptop to automatically shut down. Still with the charger unplugged, power on the laptop again. Do this until the battery is totally empty. Now plug in your charger and charge the battery fully. Then perform the commands steps again by running the POWER -ENERGY command. Make sure you note the differences in the last full charge details. Continuously perform these steps until the figures in the last full charge are more than 40% of the design capacity.

If using usb charger use usb port on back of desktop, not data port in front, also most laptops do not have fully powered usb ports due to battery consumption. The wall charger, or a usb charger plugged into a usb/ac adapter (like included with ipods and kindles or sold seperately) is your best bet for reliable charge.
Charging unit should have a light on it.
When charger is plugged into power source and not helicopter, the light will show you {#1} what it looks like when battery is fully charged. Typically this is steady on, and usually red. (sometimes green) When you connect helicopter to charger, the light will change (usually goes dark) to signify it is charging {#2}. When light comes on fully (or completely returns to #1) then charging is done. (Note: charging using a laptop usb or a front side data port usb can take several hours.) Watch the light on charging unit when you unplug helicopter, if it gets brighter, helicopter is not charged, plug it back in. Make sure to let battery cool for 10 minutes after every charge and 10 minutes after every flight, and never run battery all the way down. As soon as you can't maintain altitude, land and power off. Fully draining a Li/Po battery weakens it's ability to hold a charge and can ruin it.
If all else fails, replacement batteries are available from Amazon and many others, they are cheap (around 5$) and very easy to install with no soldering and just a small screwdriver.
Hope this helps
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