2016 and later Lexus models are equipped with an electronic parking brake system. Before removing the rear caliper the parking brake system must be placed in "pad replacement mode" which requires the use of a Toyota tech stream scan tool or equivalent. This procedure rotates the nut inside the rear caliper piston allowing the piston to be compressed for new pads or new
Brake Disc to be installed. An alternative to the factory scan tool is to unplug the electrical connector from the parking brake actuators, ground one of the terminals on the actuator with a jumper wire and apply battery voltage to the other terminal. Keep an eye on the piston - if it travels outward (applying the parking brake), stop immediately and reverse the connections. Always replace the calipers in pairs - never replace just one of them. To remove, loosen the wheel lug nuts, raise the vehicle and support it securely on jackstands. Remove the wheels. Remove the brake hose banjo bolt and disconnect the hose from the caliper. Plug the hose to keep contaminants out of the brake system and to prevent losing any more brake fluid than is necessary. If you're just removing the caliper for access to other components, don't detach the hose. Remove the caliper mounting bolts. Remove the caliper. If necessary, remove the caliper bracket from the steering knuckle or rear knuckle. To install, reverse the removal procedure. Tighten the caliper mounting bolts (and bracket bolts, if removed) to the torque. Install new sealing washers on either side of the brake hose banjo fitting, then tighten the banjo bolt to the torque. Bleed the brake system. Install the wheels and lug nuts. Lower the vehicle and tighten the lug nuts to the torque. On 2016 and later Lexus models, apply and release the parking brake several times to actuate the caliper pistons and bring them into the proper positions.