(1) Loosen air hose 120 at air brake protecting
valve supply port FV2.
(2) Start engine (TM 9-2320-365-10).
(3) Apply service brakes (TM 9-2320-365-10).
(4) Check for presence of air at air hose 120.
(5) Shut down engine (TM 9-2320-365-10).
(6) If air is not present, go to step 17 of this
fault.
(7) If air is present, replace air brake protecting
valve (para 11-16).
(8) Tighten air hose 120 at air brake protecting
valve supply port FV2.
Change 1 2-1742.21
TM 9-2320-365-20-2