TM 9-2320-364-20-22-1755(1) Check relay spring valve No. 1 forleaks (see schematic Fig 2-45).(a) If there are leaks at relay springvalve No. 1, perform Step (2)below and replace relay springvalve No.1 (Para 12-18).(b) If there are no leaks, perform Step(2) below.(2) Apply PARKING BRAKE (TM 9-2320-364-10).VISUAL/AUDIBLE INSPECTIONWear safety goggles when performing leakage tests on valves. Failure to do so may result in serious eye injurydue to high pressure air.