2004 V6 3.9l direct upgrade replacement to LED lights

I am replacing all my OEM bulbs, upgrading to LED bulbs . . . have replaced them all . . . everything is good/working.
But upon replacing the three (3) bulbs in the brake/tail light housing . . . the LED's light up constantly, but do not operate (extra illumination) as brake lights or turn signal operation. In other words, they do not perform the extra illumination when I depress the brake pedal.
Also noticed that the front side turn signal does not work with the LED's installed either.

I put the original bulbs back in . . . everything works fine.

What am I doing wrong ???
Please advise.

wow . . . thank You for all the many, numerous responses . . . this forum is awesome . . . so many helpful, concerned, sharing responses.
Apparently, converting from OEM halogen bulbs to LED requires an in-line resistor kit to be installed because of the small electrical current draw of the LED's . . . performing a brake pedal or turn signal function simply does not register with the LED's small current draw.
I decided to install the Raxiom brake/tail light sequencers and Raxiom "slow-down" flasher module . . . and went back to the halogen bulbs . . . used the Sylvania "super bright whites" for this . . . worked like a dream.
Thanks again for all helpful tips and comments !!!