OPERATION UNDER USUAL CONDITIONS
Back prime mover slowly to front of M969A3. Maneuver prime mover so that kingpin (3) on M969A3
is in line with fifth wheel jaws on prime mover. Stop prime mover before upper coupler plate (2) of
semitailer starts to ride on fifth wheel of prime mover.
Verify M969A3 upper coupler plate (2) height exceeds height of prime mover fifth wheel. Landing
gear legs may need to be raised or lowered accordingly.
Back prime mover under upper coupler plate (2) until kingpin (3) and fifth wheel hook automatically.
Verify kingpin (3) and fifth wheel are engaged and locked. Engage prime mover parking brake.
Remove dummy couplings from M969A3 service and emergency air couplings (1). Connect prime
mover service and emergency air lines to M969A3 service and emergency air lines at couplings.
Ensure drain valve (4) on air reservoir (5) of M969A3 is closed.
Open shut off valves on air lines of prime mover.
Plug 12 volt and/or 24 volt cables from prime mover into the intervehicular 12 volt (6) and 24 volt (7)
cable connectors of M969A3.
Operate lights of prime mover to verify all stoplights, marker, and clearance lights of M969A3 are
working. Verify ABS warning indicator is not lit.
ABS light functions normally when towing vehicle and when
trailer is in blackout mode. Covering the ABS light with
tape or mud is recommended during blackout operations.