Why my 28v doesn't fully charge. when charging indicator light is red. there is 4 charge indicator. when it reach 2 green light comes on showing fully charged. you would use it for about 20 minutes and it goes dead. i try charging several times but nothing change. can you help me with this battery? thanks!!!!!!!!!!!!!!!!!!!!!!!!

Sounds like old exhausted batteries to me.

the trimmers switch may be faulty.

CHARGING THE BATTERY PACK
Battery packs for this tool are shipped in a low charge condition
to prevent possible problems. Therefore, you should
charge them until the green LED on the front of the charger
comes on.
NOTE: Batteries will not reach full charge the first time they
are charged. Allow several cycles (operation followed by
recharging) for them to become fully charged.
CHARGING A COOL BATTERY PACK
See Figure 3.
If battery pack is within normal temperature range, the red
LED on charger will come on.
NOTE: If the charger does not charge the battery pack
under normal circumstances, return both the battery pack and
charger to your nearest Ryobi Authorized Service Center for
electrical check.
n Charge the battery pack only with the charger provided.
n Make sure the power supply is normal household
voltage, 120 volts, 60 Hz, AC only.
n Connect the charger to the power supply.
n Place the battery pack in the charger aligning raised rib
on the battery pack with the groove in the charger.
n Press down on the battery pack to be sure contacts on
the battery pack engage properly with contacts in the
charger.
n Normally the red LED on charger will come on. This
indicates the charger is in fast charging mode.
n Red LED should remain on for approximately 1 hour
then the green LED will come on. Green LED on
indicates battery pack is fully charged and charger is
in maintenance charge mode.
NOTE: The green LED will remain on until the
battery pack is removed from the charger or charger is
disconnected from the power supply.
n If both yellow and green LEDs come on, this indicates
a deeply discharged or defective battery pack.
Allow the battery pack to remain in the charger for 15
to 30 minutes. When the battery pack reaches normal
voltage range, the red LED should come on. If the
red LED does not come on after 30 minutes, this may
indicate a defective battery pack and should be
replaced.
n After normal usage, a minimum of 1 hour of charging time
is required to fully recharge battery pack.
n The battery pack will become slightly warm to the
touch while charging. This is normal and does not
indicate a problem.
n Do not place the charger and battery pack in an area of
extreme heat or cold. They will work best at normal room
temperature.
NOTE: The charger and battery pack should be placed
in a location where the temperature is more than 50°F
but less than 100°F.
n When batteries become fully charged, unplug the
charger from power supply and remove the battery
pack.
Source(s):http://toolboyworld.com/eBay/Ryobi_P110/...

Leave it plugged in for 4 hours. Yello should turn red then green when fully charged

Janice check your charger it could not be charging the batteries. Now always charge your batteries overnight while you sleep When you get up lights on the charger should be red and green if they are red and yellow then the charger hasn't fully charged the batteries and overnight should be more than enough time to charge fully. This could indicate a bad battery remember new doesn't always mean good. Like they say always charge before use and this goes for new batteries too you need to charge new batteries nightly for 10-15 days before they start operating at 100%. If when you plug in the charger before bed and the lights are red and green then there is a problem with the charger or the batteries or the charger circuit Hope this helps you

Your batteries are at the end of their rope and need to be replaced. All batteries die, some sooner, some later. And if you do not maintain them in a manner consistent with directions they will fail sooner!

The green light on the charger usually indicates that the batteries are fully charged and you are ready to go. Does the controller show the batteries are fully charged? Can you operate the power wheel chair for several hours? If so, you are good to go.
When you connect the charger, if the light goes to red to green within a few minutes and the battery power does not last more than 1-2 hours or less, it may indicate that that the batteries will not take a charge anymore and need to be replaced.

2 - 3 red lights indicate not fully charged. Green light = fully charged.

Not fully charged does not mean it will not function. For best results, your device should be fully charged. If you have an emergency and are not fully charged, it will not hurt to try to help with a partial charged device IMHO

Thanks for posting at FixYa.com

xenion pure shinewave inverter not charging fully

When batteries are placed into the charge mode, the red light will come on.
When fully charged, on those units with a green light, the green light will be an indication that your batteries are charged and if your unit has no green light, the fully charged indication will be when the red light turns iff.

the steady red light showing when in charger shows that
it is charging. the blinking red light when taken out of
charger or turned on and off means it is not fully charged.
leave it in charger till red light turns green.