Pronto m51 sure step controller lights flashing won't run

SOURCE: How do I charge My Pronto M51 motorized wheelchair?

I also have a Pronto M51 and use it daily. I have found though by leaving the charger plugged in over a weekend, it reduces the battery range and does not come back to normal until I use it for a week and charge it nightly. You can overcharge the batteries because the charger does not shut off entirely. I have monitored this with my meter.

SOURCE: pronto M51 ...the yellow light is blinks and dosen't stop

Take your drive units both out of gear and put them back in that will reset the computer and it started mine working again.

SOURCE: tool; light blinks 9 times battery is charged

the batteries were dead

SOURCE: sure step m51 lights flashing

The year info is the 1st 2 digits of the serial number. The S/N is located on a Mfg's sticker afixed to the frame of the chair.

Are you sure it's in gear?

SOURCE: someone gave me a pronto m51 sure step motorized

Jo, nope you are safe. Most of the chargers are designed to cut off and go into trickle charge once they sense that the batteries are fully charged. The problem with overcharging comes after 18 hours or so. You should never leave the charger plugged into the chair for more than 24 hours. On the M51 the charger is built into the chair so just plug it in when you go to bed and unplug it when you get up and you'll be ok. You can check for full charge by looking at the charger there should be a red light and a green light when fully charged. Hope this helps