TM-9-2320-272-24-1

TRUCK, 5-TON, 6X6, M939, M939A1, AND M939A2 SERIES TRUCKS (DIESEL)

TECHNICAL MANUAL; UNIT, DIRECT SUPPORT, AND GENERAL SUPPORT MAINTENANCE MANUAL; VOLUME 1 OF 4

JUNE 1998

TM-9-2320-272-24-1 - Page 306 of 1015

TM 9-2320-272-24-1

Table 2-4. Compressed Air and Brake System Troubleshooting (Contd).

MALFUNCTION

TEST OR INSPECTION

CORRECTIVE ACTION

24. HORN DOES NOT WORK (GAUGES AT NORMAL OPERATING PRESSURE, WARNING BUZZER NOT

SOUNDING)

Step 1.

Check air supply at air electric valve (1).

Step 2.

Loosen supply line (2) slowly.

a.

If air is not heard escaping, repair or replace supply line (2) (TM 9-243).

b.

If air is heard escaping, perform Electrical Troubleshooting, para. 2-22.

END OF TESTING!

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