LG 4010 Charging problem?

I have had my LG 4010 for over 4 yr and now it won't indicate a full (bars) charge while I am trying to charge it. The charger red led light is on. I suspect several things, either one end or the other of the charger has some bad wiring, the phone end of the charger has bad terminals, the phone itself has bad terminal connection or the phone battery has gone bad all at once and won't show a current charging status. I don't know how to determine the cause and I don't have another charge cord or battery for this model/brand. Please advise me as to what could have gone wrong even though the charger LED light is lit ???
I will be waiting for some assistance,
Thanks
kourso
kourso@cox.net