Power Application And Preflight Tests - Honeywell KAP 140 Installation Manual

Power Application and Preflight Tests

KAP 140 Preflight Test
KAP 140 Preflight Test Complete
A preflight test is performed upon power application to the computer. This test is a
sequence of internal checks that validate proper system operation prior to allowing
autopilot engagement. The preflight test (PFT) sequence is indicated by "PFT" with an
increasing number for the sequence steps. Successful completion of self test is identified
by all display segments being illuminated (Display Test) and the disconnect tone sounding.
Following the preflight test, the red P warning on the face of the autopilot may illuminate
indicating that the pitch axis cannot be engaged. This condition should be temporary,
lasting no more than 30 seconds. The P will extinguish and normal operation will be
available.
Red P and R warnings may illuminate when the autopilot is not engaged. This can occur
when autopilot G limits have been exceeded during turbulence or aircraft maneuvering.
Autopilot engagement is locked out during red R illumination.
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