I bought 2 P103 lithium batteries and they will not take a charge from my one + (p110) charger. I was informed that these components are all interchangeable. Will the P103s work with the blue 18v ryobi tools I already have at least?

check output on transformer, 2 check pcb ,could be a regulator

No, the P110, 18V NiCad battery charger, will not charge a 18V lithium ion battery. You need one of the dual-chemistry chargers. If you have the Ryobi ONE+ batteries, you can get the P117 charger ($30) or a charger with an extra battery (P126) from a store like Home Depot. A 6 battery charger and a 12V in-car charger are also available.

I wish that I had better news for you.

Cindy Wells
(who has the Ryobi 12V drill and charger, a few of the 4V tools, and a number of the ONE+ 18V devices and chargers. The single chemistry battery charger is not used much any more.)

make sure you put the battery in the right way and its all the way down in the charger

p103 is name of the battery. p106 is the kit with 2 p103 batteries. same thing just 2 times. the p104 however is bigger and holds more juice.

time for new drill and batts

If you have a P100 NiCad battery, the charger for that will not charge the new Lithium Ion P103 or P104 batteries. You need a specialised Ryobi Lithium Ion battery charger like this one

No. The P110 is for NiCad batteries. Any of the Li-Ion chargers like the P113 are backwards compatible and can charge either but do not try to charge Li_ion batteries in a NiCad or NiHi charger.

You need to have the charger tested, if you know that batteries are good then what else could it be. This LIon charger has a logic circuit in it like a computer.

If you are sure your charger is working properly then your one battery may be shot.. i even had a new battery quit charging and had to replace it. they do not come cheap.

Yes you can that is an automatic charger when it is fully charged it shuts down the charging portion but keeps the charged light lit however this does not effect the battery.