ABS Light Issues - Code C1421 - Anyone have diagnostic info?

Code says - Open or Short in Master Cylinder

Looking for some help or if anyone has access to diagnostics for this code, not much information when googling.

Repair shop says I need to replace the entire Brake Booster Pump Assembly on my 16 TRD OR.

$1800 for the part and another $900 for install and Techstream calibration.

 

C1421 Open or Short in Master Cylinder Pressure Sensor Any of the following is detected:

• When voltage at terminal +BS is 9.5 V or higher, power supply voltage of master cylinder pressure sensor is continuously low for 1 second or more.
• When master cylinder pressure sensor power supply voltage has risen, master cylinder pressure sensor has overheated or overcurrent of master cylinder pressure sensor continues for 0.1 seconds or more.
• When +BS terminal voltage is 9.5 to 17.4 V, there is no communication with master cylinder pressure sensor continuously for 0.1 seconds or more.

Brake actuator assembly (Master cylinder pressure sensor)

 

Thanks. I was hoping I had a ground short somewhere but appears it is internal in the pressure sensor.