TM 10-3930-669-20 7-17.  MASTER CYLINDER PRESSURE SWITCH REPLACEMENT (CONT). b.  Installation. WARNING Brake fluid, lubricants, and other chemicals  can  cause  serious  injury  to eyes.    If  your  eyes  are  effected,  flush immediately  with  cold  water  and  seek medical attention. (1) Install pressure switch (3) on fitting (4). (2) Connect   brake   switch   connector   (2)   on connector P21 (1). NOTE Follow-on Maintenance: • Close engine access panel (TM 10-3930-669-10). • Close  cab  door  (TM  10-3930-669- 10). • Connect batteries (Para 7-48). • Remove wheel chocks (TM 10-3930-669-10). END OF TASK 7-38