I had to replace my old jobemate 12v battery. With the new one I put it in the charger, but after 16h the red light is still on ..... is there an issue with the battery .... I no longer have the manua

Completely dead batteries may cause the charger to not see any load and it wont charge them. The way around this is to put the battery on the charger with the charger unplugged. Then plug in the charger and check the lights. Keep unplugging and plugging in the charger till it catches up and stays on.

17 volts is a sign of one battery bad, or both. How old are the batteries? Check each battery separately for at least 12v. Check at the batteries themselves. If you don't get the 12 or greater reading replace the batteries. If you don't have insurance check at batterysharks.com.

Bad Battery pack, check voltage, try jumping nickel/cadmium battery with car charger, then put on charger.

Either the charging adapter is faulty or the battery is worn out.

If the recharageable battery is more than 3 - 4 years old then the battery could be worn out.Rechargeable batteries have a finite number of charge and discharge cycles andwill lose their charge capacity over time, i.e. won't charge to 100% andgradually the charge reduces until the battery won't charge up at all. OR Thebattery shows a 100% charge but when the adapter is disconnected the batterydrops off to zero capacity in a very short time. If the battery drops to anunacceptable charge level then the battery needs to be replaced.

Product Detail Model No.: HB-1206S
The item is used for charging 6V-12V lead-acid batteries
Max Charging Current: 6A
AC Power Input: 64W
Output: 6/12V DC 3. 52A
Batteries Capacities: 15AHR-80AHR
Unit Packing: Colorful box
Dimension: 18cm x 10cm x 20cm
G. W. / N. W.: 1. 85KG/1. 75KG
Certifications: GS, CE, BS, ROHS, SAA

Main functions:
(1) The HB-1206S battery charger has the features of convenient operations, reliable safety and high performance.
(2) During charging, if turn up overload, the battery charger will keep itself at normal current and normal voltage with its self-automatic protecting function.
(3) If being short circuit, the battery charger will switch off itself, and turn normal after one or two minutes.
(4) The output current of the battery charger is very stationary, so it can protect the battery charger very well. It only costs 3 or 4 hours to fully charge the batteries.
(5) Indication of charging: the battery charger has 6 pilot lamps. The more pilot lamps shining, the less electric quantity is. The charging process finishes when all the pilot lamps go out.
(6) The battery charger can be switched between 6V and 12V, so it can charge for 6V and 12V accumulators. You can select 6V or 12V according to your own needs.
(7)The operations are very convenient: Put the red clip to the positive pole of the accumulator which indicated "+", and put the black clip to the negative pole of the accumulator which indicated "-", then plug in power source, the accumulator will be charged.

Batteries are only good for about a year, if they are older than that, take them back to the store and see if they are guaranteed at all, (all Ryobi tools and batteries have a date code on them, and they are all guaranteed for 2 years, a little plug for Ryobi,) that is all I buy now days, they work great. So, to check your charger, you will need a volt meter set on 12 or 20 v dc, and see if the charger is putting out, if not, then, the cost of a new ryobi might be the same as the fix for the black and decker. That is if you use the thing, we use our cordless tools every day and charge them every night, hope this helps.

What type and what voltage were the old batteries removed from the scooter?

The battery is gone for sure... You must get new one... take a look on amazon (my recommendation): Amazon com nailers paslode battery

I really don't have any idea as to what you're talking about here other than a battery and maybe a charger. Seems as if you're saying that you have a 12 volt 1.5 amp automatic battery charger connected to a 12 volt, 8.5amph battery but the red light on your charger is blinking. The blinking red light indicates that the charger is not seeing a proper connection such as crossed polarity connection or simply a poor connection. You say that the battery voltage has dropped from 12.5 volts to 9.1 volts with the charger connected. If this is the case, the battery is badly discharged and the charger is not charging the battery for some reason. The charger may be bad but check the connections to make certain they are correct and good. If they are, I'd replace the charger.

Good luck
Steve