Getting ABS codes 22 and 21

Code 21 is right front ABS solenoid circuit.
Code 22 is left front ABS solenoid circuit.
Check the ABS actuator (control unit) wire harness for cleanliness and tight connections. Such problems are usually due to a faulty control unit if the wiring circuits are good.

Sensors seldom fails in tandem and the most likely cause would be the control unit, meaning the ABS module needs to be replaced.

Before replacing the control unit, you need to be sure that the sensors and its wiring are not the ones at fault. You mentioned testing with used sensors, how sure are you that they are good?
If you read the live data, you should be able to understand if the sensors are working. Lift up front of vehicle and get somebody to turn each wheel while you read the live data of the sensors.

Sorry for the delay in getting back to you. I have delved deeper into this and here are the testing procedures. It is the solenoids and not the sensors that are causing the problem. Go through the testing procedures and see what comes up.

DTC C0226/21: RIGHT FRONT ABS SOLENOID CIRCUIT, DTC C0236/22: LEFT FRONT ABS SOLENOID CIRCUIT, DTC C0246/23: RIGHT REAR ABS SOLENOID CIRCUIT OR DTC C0256/24: LEFT REAR ABS SOLENOID CIRCUIT

CAUTION: If Anti-Lock Brake System/Traction Control/Vehicle Skid Control Electronic Control Unit (ABS/TRAC/VSC ECU) replacement is necessary during testing, always ensure ABS/TRAC/VSC ECU connectors and ground circuit are okay. If either is suspect, repair and repeat testing to confirm ABS/TRAC/VSC ECU malfunction.

Circuit Description
ABS solenoid turns on when signal is received from ABS/TRAC/VSC ECU. Solenoid controls fluid pressure acting on brake calipers. DTC is set when system is operating and ABS/TRAC/VSC ECU detects an open or short circuit in ABS solenoid circuit for.05 seconds or more. If a fault occurs in ABS solenoid circuit, ABS/TRAC/VSC ECU performs a fail safe function, turning off current to ABS solenoid relay and prohibiting ABS, TRAC and VSC. Possible causes are:

ABS/TRAC/VSC Actuator
Open Or Short Circuit
ABS/TRAC/VSC ECU

Diagnosis & Repair
Remove air cleaner and battery clamp cover to gain access to ABS/TRAC/VSC actuator. Disconnect ABS/TRAC/VSC actuator connectors. Check resistance between terminal No. 4 at ABS/TRAC/VSC actuator A34 connector and specified terminals at ABS/TRAC/VSC actuator A36 connector. See ABS SOLENOID RESISTANCE CHECK table. See Fig 1. If resistance is as specified, go to next step. If resistance is not as specified, replace ABS/TRAC/VSC actuator.
ABS SOLENOID RESISTANCE CHECK

ABS/TRAC/VSC Actuator A36 Connector Terminal No. Ohms
2 8-10
3 3-6
4 8-10
5 8-10
6 3-6
7 3-6
10 3-6
12 8-10
(1) Measure resistance between terminal No. 4 at ABS/TRAC/VSC actuator A34 connector and connector A36 terminals listed. See Fig 1.
Fig 1: Testing ABS Solenoid Resistance At ABS/TRAC/VSC Actuator
G98G13009
Courtesy of TOYOTA MOTOR SALES, U.S.A, INC.
Disconnect ABS/TRAC/VSC ECU harness connectors. ABS/TRAC/VSC ECU is located behind right kick panel. See Figure. Check for open or short in ABS solenoid circuits between ABS/TRAC/VSC actuator and ABS/TRAC/VSC ECU. See ABS SOLENOID CIRCUIT CHECK table. See Figure and Fig 1. Repair wiring as necessary. If wiring is okay, clear DTCs. See CLEARING DIAGNOSTIC TROUBLE CODES under DIAGNOSIS & TESTING. Test drive vehicle and retrieve codes. See RETRIEVING DIAGNOSTIC TROUBLE CODES under DIAGNOSIS & TESTING. If code is still present, replace ABS/TRAC/VSC ECU.
ABS SOLENOID CIRCUIT CHECK

ABS/TRAC/VSC Actuator A36 Connector Terminal No. Wire Color ABS/TRAC/VSC ECU Connector (Terminal No.)
2 Blue/Red A38 (21)
3 Blue A41 (8)
4 Yellow/Black A41 (16)
5 Violet/White A41 (7)
6 Yellow A38 (9)
7 Light Green/Red A38 (7)
10 Blue/Black A41 (1)
12 Red A38 (21)