Battery Light On

[Lorenzo]

i know this topic has been discussed THOUSANDS of times. I promise i wouldnt be here if i didnt need to.
2010 Toyota Camry SE
battery light on and battery draining. obviously the car is running off the battery. It slowly discharges and dies out.
Owner had a friend replace the alternator and battery. Problem was still happening.
She brought it to me and i took the alternator off and had it tested at autozone, turned out bad. Replaced with a brand new one, (warranty item) and still doing the same. I checked the alternator fuse (pain in the a$$ to remove) and its good. not blown.
Only thing i can think of is the voltage regulator but its on the ecu. do i call it on the ecu and break out the bad news yet? or is there something that i missed to check? belt is good and snug running through the pullies as they should. No corrosion or loose wires. Multimeter shows the battery at 12.4 with car off. and started, it starts draining slowly. theres a weird 3.xx volts reading on the wire thats bolted to the alternator. Any ideas or anything i overlooked? Already checked off almost everything on etcg videos and forums.

Topic

[zero]

If the alternator was of the same brand bought at nearly the same time that the other DOA one was, there’s a decent chance that it’s also DOA. The odds go up the cheaper the rebuilt unit is.

On some cheap reman’d units, there is a known issue with them not recognizing the input from the ECU that tells them to charge. If you can find a wiring diagram, the signal wire is likely on a 5v scale. All you can really do with limited resources is confirm alternator function and the continuity of the wires controlling the alternator.

[Richard Kirshy]

See if this is of any help:
http://www.autoshop101.com/forms/elec05.pdf

[Author]

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