TM-9-2320-279-20-1

M977 SERIES, 8x8 HEAVY EXPANDED MOBILITY TACTICAL TRUCKS (HEMTT)

TECHNICAL MANUAL; MAINTENANCE INSTRUCTIONS; ORGANIZATIONAL MAINTENANCE, VOLUME 1 OF 3

TM-9-2320-279-20-1 - Page 258 of 985

TM 9-2320-279-20-1

Troubleshooting Malfunctions (Cent)

Tdde2-9. Trouf,deshooting (Cent)

Malfunction

Test or Inspection

Corrective Action

DUAL AIR BRAKE SYSTEM (CONT)

1.

BRAKES WILL NOT RESPOND PROPERLY (CONT).

BRAKE

TREADLE

VALVE

STOP

LIGHT

SWITCHES

Step

8.

Check for defective brake treadle valve. Remove both stoplight switches from brake treadle

valve. Apply service brakes and listen for air escaping from brake treadle valve stoplight

switch holes.

If air is not heard escaping from both holes, replace defective brake treadle valve

(para 11-10).

If air is heard escaping, inspect double check valve in line No. 489 (all models) or

in line No. 489A (M984E 1 only) for damage. Replace damaged double check valve

(para 11-14 or 11-15).

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