It is important to know about the elements related to system and equipment malfunctions appropriate to the airplane provided for the practical test.
PHAK Ch-07 Aircraft Systems
AFH Ch-17 (11) Systems Malfunctions
C-172 PIM Section 7 Airplane and Systems Description
406 ELT Handout
NTSB 830.5
Initial Notification of Aircraft Accidents, Incidents, and Overdue Aircraft
C-172S: Emergency Procedures
C-172S: Abnormal Procedures
Private Pilot ACS Page 52 Task C. Systems and Equipment Malfunction