TM-9-2320-272-23-1

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

TECHNICAL MANUAL; FIELD MAINTENANCE MANUAL; VOLUME 1 OF 5

SEPTEMBER 2012

TM-9-2320-272-23-1 - Page 1116 of 1313

FIELD MAINTENANCE

PRIMARY AIR SYSTEM FAILS TO MAINTAIN PRESSURE (NO MAJOR LEAKS, AIR CAN BE HEARD

ESCAPING INTO AIR INTAKE STACK, PARKING BRAKE APPLIED)

INITIAL SETUP:

Tools and Special Tools

Tool Kit, General Mechanic's: Automotive

(Volume 5, WP

0826, Table 1, Item 56)

Test Set, Electronic Systems

(Volume 5, WP

0826, Table 1, Item 51)

Personnel Required

(2)

References

Point to Point Schematics

Volume 3, WP

0434

Equipment Condition

Vehicle parked and engine shut down.

(TM

9-2320-272-10)

TROUBLESHOOTING PROCEDURE

PRIMARY AIR SYSTEM FAILS TO MAINTAIN PRESSURE (NO MAJOR LEAKS, AIR CAN BE HEARD

ESCAPING INTO AIR INTAKE STACK, PARKING BRAKE APPLIED)

NOTE

Conduct these malfunction tests if primary air pressure system fails to hold pressure. No

major leaks, air can be heard escaping into air intake stack, parking brake applied. This

procedure will check for air leaks through vent lines.

TM 9-2320-272-23-1

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