TM 5-2350-378-23&P
0025
Table 4. Possible Symptoms Of Failed HDC System Components.
HDC SYSTEM
POSSIBLE CONSEQUENCES
NOTE
The probability of a stuck solenoid valve is low and would occur after a hydraulic
maintenance test is performed where a solenoid valve was energized (to change status)
as part of a specific test.
Numbers in parentheses (possible consequences) correspond to vehicle hydraulic line
Cannot extend ejector cylinder or cannot retract
Solenoid Valve V-1 - Shutoff valve - ejector control valve
ejector cylinder.
extend
Cannot dump load or cannot retract ejector to fill
load.
Cannot fold or unfold apron.
Solenoid Valve V2 - Shutoff valve - No. 1 actuator right
SPRUNG MODE:
front
No hydraulic fluid return (11) from right front
wheel valve.
Wheel valve stays in unsprung position.
No hydraulic fluid supply (9) to right front
actuators 1 & 2.
Front right of vehicle will not be raised.
Right front of vehicle will drag or bottom out.
No suspension shock absorbing capability on
right front side.
UNSPRUNG MODE:
No hydraulic fluid supply (11) to right front wheel
valve.
Wheel valve stays in sprung position.
No hydraulic fluid return (3) connection from
actuators 1 & 2 to DCV.
Undesired hydraulic fluid supply (9) to front right
actuators 1 & 2.
Right front of vehicle is raised to sprung position.
Undesired suspension dampening on right front
side.
UNSPRUNG-LOWER:
No hydraulic fluid supply (17) to front right
actuator 1.
No hydraulic fluid return (3) from right front
actuators 1 & 2.
Front right of vehicle will not be lowered.
03/15/2011Rel(1.8)root(maintwp)wpno(M10001)