Cessna SkyHawk SP 172S NAV III 2005 Pilot Operating Handbook page 351

SECTION 9 - SUPPLEMENTS
SUPPLEMENT 3
NORMAL PROCEDURES
CESSNA
MODEL 172S NAV III
PREFLIGHT (PERFORM BEFORE EACH FLIGHT):
1. MASTER Switch (BAT) - ON.
2.
AVIONICS Switch BUS
2 -
ON.
3. POWER APPLICATION and SELF-TEST - The autopilot
tests itself when power is first made available. The test is a
sequence of internal checks before starting normal system
operation. The test sequence is shown on the face of the
autopilot as IIPFT XII.
IIX II is the test sequence step
number. Successful completion of the self-test is shown by
all autopilot display elements coming on (Display Test), the
PITCH TRIM annunciator on the PFD coming on and the
operation of the autopilot disengagement tone.
WARNING
IF THE RED P STAYS ON, THE AUTOPILOT HAS
FAILED THE PREFLIGHT TEST. OPEN (PULL) THE
AUTO PILOT CIRCUIT BREAKER TO MAKE SURE
THAT THE AUTOPILOT AND MANUAL ELECTRIC
TRIM SYSTEM WILL NOT OPERATE.
NOTE
When power is first supplied to the autopilot, the red P
(pitch trim) lamp on the face of the autopilot may come
on to show that the pitch system cannot be engaged.
This condition should last approximately 30 seconds.
The P will go off and the autopilot pitch trim system will
function correctly.
(Continued Next Page)
S3-22 U.S.
FAA APPROVED
172SPHAUS-S3-00