TB-9-3950-253-13-P

PALLETIZED LOAD SYSTEM TRUCK, M1075 and M1075A1 (PLS) AND HEAVY EXPANDED MOBILITY TACTICAL TRUCK, M1120, M1120A2, AND M1120A4 (HEMTT), ENHANCED CONTAINER HANDLING UNIT (E-CHU)

TECHNICAL BULLETIN; OPERATOR AND FIELD MAINTENANCE, INSTALLATION INSTRUCTIONS, AND REPAIR PARTS AND SPECIAL TOOLS LIST

JULY 2009

TB-9-3950-253-13-P - Page 211 of 704

0019-31

Change 1

TB 9-3950-253-13&P

0019

PNEUMATIC SYSTEM - CONTINUED

1. NO STOWAGE LATCH FUNCTION – CONTINUED.

NOTE

•

P3 has 24V only when STOW or RETRIEVE button on control panel is activated.

•

When ignition switch is turned on after battery disconnect switch has been turned off and

back on, error codes 1 and 24 may alternately display for one minute. This error code

indicates that temporary settings were lost while battery disconnect switch was off, and is

consistent with normal operation.

Step 4.

With engine on, press RETRIEVE button on control panel and check for 24V supply on P3 pin 1

and 2 in relay box.

a.

If no 24V, replace relay box (WP 0029).

b.

If 24V, proceed to next step.

Step 5.

Set ignition switch and battery disconnect switch to OFF position (PLS: TM 9-2320-364-14&P,

HEMTT: TM 9-2320-326-14&P).

Step 6.

Disconnect stowage latch harness from solenoid valve (WP 0026).

Step 7.

Set ignition switch and battery disconnect switch to ON position and start engine.

Step 8.

Press STOW button on control panel and check for 24V supply between pins 1 and 2.

a.

If no 24V, replace stowage latch harness (WP 0026).

b.

If 24V, set ignition switch and battery disconnect switch to off position and proceed to Step

9.

Step 9.

Relieve air system pressure (PLS: TM 9-2320-364-14&P, HEMTT: TM 9-2320-326-14&P).

Step 10.

Disconnect air input hose from valve actuator and connect test gauge hose to input hose.

Step 11.

Set battery disconnect switch to ON position and start engine.

Step 12.

Press STOW button and check input pressure. Air input pressure should be 130 psi.

a.

If input pressure is less than 130 psi, refer to vehicle TM (PLS: TM 9-2320-364-14&P,

HEMTT: TM 9-2320-326-14&P).

b.

If input pressure is 130 psi, turn off engine, relieve air system pressure and proceed to Step

13.

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

0.