Depending on the year of manufacture, the attachment points may differ.
Front bumper
-open the hood.
-under the hood take out the caps and remove the trim over the grille.
-under the trim, Unscrew the screws that secure the upper part of the bumper and grille.
-in the front of the bumper, below the grille, Unscrew the two screws
-at the bottom of the bumper, Unscrew the screws and take out the caps (twisted and inserted from the bottom up).
-turn the wheels to the side.
-in the wheel arches we take out the caps that attach the fender liner (front) and the corners of the bumper to the wings.
-we release the latch in the wings (pull the corners of the bumper towards you).
-with an assistant, pull the bumper forward (look for the wires).
-disconnect electrical connectors.
Rear bumper
-open the trunk lid.
-in the opening of the trunk, Unscrew the four screws (or six, depending on the type of body and year).
-at the bottom of the bumper take out nine caps (inserted from the bottom up).
-in the wheel arches, we release the fender liner (rear part) and take out the caps that attach the corners of the bumper to the wings.
-we release the latches in the wings and under the rear lights (pull the corners of the bumper and the sides of the lining towards you).
-with an assistant, pull the bumper back (look for the wires).
-disconnect electrical connectors (if any).
How to remove the front and rear bumper Toyota Alphard (2002-2008)
How to remove the front and rear bumper Toyota Alphard (2008-2015)