(1) Loosen air hose 124 at air brake protecting
valve control port TRA E.
(2) Start engine (TM 9-2320-365-10).
(3) Push in TRAILER AIR SUPPLY control
(TM 9-2320-365-10).
(4) Check for presence of air at air hose 124.
(5) Shut down engine (TM 9-2320-365-10).
(6) If air is not present, go to step 6 of this fault.
(7) If air is present, replace air brake protecting
valve (para 11-16).
(8) Tighten air hose 124 at air brake protecting
valve control port TRA E.
Change 1 2-1742.5
TM 9-2320-365-20-2