ATC light help

The ATC lights is finally get steady on. I checked with AcomDiagnostic it's says PS2 brake demand pressure sensor circuit is faulty. Grounded or shorted to the +5 volt. On ABS module socket X4 pins 1, 4, 6. Tracing circuit on Volvo electrical diagram to figure out where sensor is but diagram says it's not sensor it's valve Y100.
How to find this sensor?

 

SOLVED!
First of all I got old brain farting and bad eyes. The pin is not # 6. It's pin #5 sensor signal. Two sensors marked as E1 and E2 are respectively brake pressure in front and rear. Connected E2 plug to E1 sensor and faulty code changed to SP1 from SP2 sensor. Sensor E2 itself is bad. My luck the wires or ABS module are good.