OPERATING THE APU - Continued
6 .While holding PREHEAT switch ON, position and hold START switch (5) to
MOMentary ON. Hold both switches ON until APU engine starts.
if APU engine doesnt start within one minute, release
START switch (5), but continue to hold PREHEAT switch
ON for another 20 seconds (in temperatures above 55° F)
or one minute (in temperatures below 55° F). After allotted
time, hold START switch ON again. If engine still does not
start, troubleshoot APU (p 3-11).
7. When APU starts, release PREHEAT switch and START
To avoid damaging the APU engine, if oil PRESSure
lamp (3) remains lit after engine starts, or if it lights
during APU operation, turn FUEL SHUTOFF switch
(2) OFF to stop APU. Notify Organizational Mainte-
nance if this problem occurs.