Batboard

I have 4 impress chargers that are not working, they have power coming to them but the charging led will not come on. Is there a way to fix these, are there any common problems with them or is it just best to replace the charger base. Would there be any software issues that could be looked at on the charger that would fix it?

motorola will not release the schematics on these newer chargers.. have the same problem too.. hafta do voltage comparison with another good charger