B41a

[b41ade]

Hi guys.

Ive just been given  2x 18v xr 4ah batteries.

1x works fine and has just over 18v across the terminals.

The other has 20.2v but wont work. It only illuminated the led for aprox 1 second then nothing.

Any suggestions please

[b41ade]

Sorry. I forgot to say all my tools are the 18v xr platform

[Eric - TIA]

Check to see if your 18V platform is compatible with the 20v battery.  I would think it is, but for some reason, I thought the older Dewalt is not backward compatible, but I am probably wrong.  Do all LED lights go on the 20v battery or just one of the led lights?  What happens when you put it on a charger?

[b41ade]

All the leds flicker on then off.

The battery is showing full charge and charged without issue.

The label just says 18v xr not 20v max so im presuming its meant to be an 18v xr setup.

My xr kit is aprox 10 years old but the battery is dated 2015 so i thought shouldnt be an issue