2015 avalon with the v6

I have this car with the battery light on all the time when the car starts. I got this car brought in and the alternator is new and ecm is new too. Alternator is charging between 14.2 and14.4 I do not know how to trouble shoot this light since it doesnt have any codes present. It does have a sign saying charging system problem and battery light on dash.
Something i did was to disconect the alternator plug and the light goes away from the dash but alternator stops charging. I do need help so anyone that has had an issue like this or can help me would be awesome. Thank you fam.
PD it has new alternator from autoone and used ecm already programmed. Cant erase the light 

It has been my experience that issues like this usually come down to inferior parts.
I would be willing to bet the new alternator is at fault. Disconnecting the connector and the charging system light going off is a good indication the circuit for the lamp is not shorted to ground and that the instrument cluster is working

Hey Bruteza! FYI, I moved your thread to the Repair section.

I'm happy to go into details about pinpoint testing this alternator with you, but honestly, I think you're done. You stated the battery light is on at idle but charges normally. Light goes off when you unplug the alternator. That means the alternator is grounding the light control circuit when it shouldn't be. The 'Zone alternator sucks. Consider a different brand of parts jobber, or skip the BS and just get one from the dealer.

If you want to prove it out, unplug the alternator and check for 10-12V on the L terminal, engine running. Now use an incandescent test light connected to B- and gently touch the L terminal. Can you make the battery light come on? If so, you've shown the light circuit works normally. Alternator time.

 

S - 12V
IG - 12V
M - Doesn't matter.

Hey thank you so much! I’ll try this and get back to you. You are awesome

So I checked like you said. Battery light come on when I use an incandescent light connected to battery - and gently touch the the terminal.
I went ahead and replaced the alternator from one that I got at the dealership. Lights still showing there at the instrument cluster. Never goes off . What I see on the 3 wires that are connected to the alternator.
Alternator connector disconnected and engine running at idle
A wire 12v
Another wire 2.56 v
Another wire I see nothing no voltage or ground

That's disappointing. 

Do you recall what voltages you saw on which wires? Based on the voltage readings you mentioned, you're missing at least one 12V fused feed. Green and violet should be 12V with the key on. Pink is the light circuit, which you already checked. Blue is a pulse width load input to the ECM and won't cause the battery light to come on.

 

MAKE SURE G AND V WIRES HAVE 12V