How do you check the battery charger?

Here's a link to a bunch of replacement chargers....

https://www.google.com/search?q=Invacare+M51+Surestep+replacement+charger&newwindow=1&sxsrf=APwXEddmA91gRXeJPK8JzJf9dHNyEAAvMQ%3A1682171313277&source=hp&ei=seVDZLTIDv3OkPIPkd-S8Ag&iflsig=AOEireoAAAAAZEPzwSyXMv34ozadubH2bPfwxcQtlSi0&ved=0ahUKEwj05M680L3-AhV9J0QIHZGvBI4Q4dUDCAs&uact=5&oq=Invacare+M51+Surestep+replacement+charger&gs_lcp=Cgdnd3Mtd2l6EAMyBQghEKABMgUIIRCgATIFCCEQoAE6BggAEBYQHjoICAAQigUQhgM6BQghEKsCUABYglVgkFpoAHAAeACAAe0BiAGGGJIBBjAuMjAuMZgBAKABAqABAQ&sclient=gws-wiz

Best to you

have the charger charge rate checked as the charger may not be working to standard voltage for charging
you can do that by connecting a multimeter meter across the battery terminals and turning on the charger
the voltage should go from 12 volts to 14.5 volts indicating a charge is being put into the batteries
if you don't get that increase when turning the charger on , then there is something wrong in
battery connection, charger
wiring
fuse

Charging a battery requires two components. A working charger and a functioning battery. The concept is simple. A battery charger must output more voltage than the battery does, and at an acceptable current level. First determine the battery output from the ID sticker, then measure the charger output. It must be 1 or 2 volts more than the battery output. If the charger is working, charge the battery overnight. If the battery does not charge or runs down quickly, the battery must be replaced. All batteries have a limited number of charge cycles. The most common problem with Ni-Cad batteries happens when they are re-charged before they are completely discharged. Recharging a half used Ni-Cad sets up a short term memory and the battery discharges faster than normal.

Should use proper 24 volt 2-4 amp off-board charger. A 3 red, 3 green flash code on a VSI/Remote Plus controller indicates high battery voltage.

The batteries are low and need charging If after you charge and you still have the single red light then you need to replace the batteries

Do you have a volt meter so that you can check battery output when unit is running. The charge rate on most small engines is about 3 amp so it will not charge very fast. If you have a battery charger I would disconnect negative cable from battery, check voltage on battery then hook up charger for a couple hours. Recheck voltage.Then leave battery neg. cable off overnight and check voltage again the next day.You may have a bad battery that wont hold charge. If it holds charge overnight then I would hook neg. cable back up and leave set for a day or two and recheck voltage. If voltage has dropped then you have something draining battery. Before I did anything to drastic I would clean all connections to battery and starter switch. If your system is really not charging you will have to replace starting diode. Good luck.

Mark Batteries your charger is putting our enuf 13.15 volts for each battery so after charging all night you should be reading about 13 volts on each. If your batts are only 12 volts after all night charge then batteries are weak Hope this helps

Hi. Always charge your batteries overnight after each use. Do not charge your batteries for days or weeks at a time unless you have a good quality automatic charger.
Most 4 amp chargers, charge the batteries up to approx 28.5 volts, and will maintain this voltage forever if left on. This will eventually shorten the life of the batteries.
The Invacare 8 amp charger is a fully automatic charger. It will take the batteries up to about 28.5 volts, it will hold this voltage for a few hours, and then drop the voltage to 27.6 volts ( 13.8 volts across each battery ). These chargers can be left on for weeks at a time.
Good luck. Neil.

Hi. To remove the batteries, it is neccessary to remove the seat first. Turn the seat a bit and then lift it straight up. Next remove the cover under the seat, it will probably be held on with velcro. Under the cover you will see the batteries. They will be held in place by fabric straps, which you will have to loosen. Make sure that the machine is turned off, unplub the batteries and remove them.
You will be the best judge of the condition of your batteries.
Can you travel as far as you used to, without the battery gauge falling further than it used to?
It is important to recharge your batteries after each trip, and to charge them overnight at least.If you haven't used the machine for a few weeks, give it a charge overnight.
Some chargers can be left on for weeks at a time, and some chargers should only be used overnight only. The reason for this is that some chargers, such as the Invacare 8 amp charger, will drop down to a float charge after charging the batteries. Most of the smaller 4 amp chargers do not drop down to a float charge, but maintain the full voltage untill they are turned of.
Good luck. Neil.

hi Richard,

Does the scooter actually lose power after the 3 leds show ?

If it is losing power then a suggest to try some other batteries to confirm dodgy batteries, check the terminal connections etc.

If it does not lose power then the volt meter is at fault, if you can check the voltage before riding then after it shows only 3 leds , if there is a big drop, check the charger first to make sure the batteries are getting fully charged.

Regards
GeWiz.,