Posted by: @humberto-flores

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2011 sienna I changed alternator twice checked 140 amp and fueses but everything looks good but the alternator is still not charging

There may be a so-called mega fuse between the alternator and the rest of the car's electrical system. My old Ranger had one. The alternator's voltage would come and go, triggering the battery light. I replaced the alternator and it did the same thing with the new one. Then, I found out there was that mega fuse. When I checked it, it was all corroded. I put in a new one and the battery light disappeared.

Check this out and see if it helps

https://carkiller.com/scottykilmer/postid/292861/

Posted by: @humberto-flores

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alternator is still not charging

How do you know?

Did you have the battery tested?

Check to see if this Toyota TSB is applicable:

https://lemon-manuals.la/Toyota/2011/Sienna%20Base%2C%20Van%20Cargo/Repair%20and%20Diagnosis/Quick%20Lookups/Technical%20Bulletins/Technical%20Service%20Bulletins/Other%20Variant/Charging%20Systems/Charging%20System%20Inoperative%20%28T-SB-0055-12%29/

The above TSB includes step-by-step charging system diagnostics.