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 718 of 1313

FIELD MAINTENANCE

ENGINE AND VEHICLE ELECTRICAL SYSTEMS MALFUNCTIONING

INITIAL SETUP:

Tools and Special Tools

Tool Kit, General Mechanic's: Automotive

(Volume 5, WP

0826, Table 1, Item 56)

Multimeter

(Volume 5, WP

0826, Table 1, Item 34)

Test Set, Electronic Systems

(Volume 5, WP

0826, Table 1, Item 51)

Personnel Required

(2)

References

Point to Point Schematics

References (cont.)

WP

0089

Volume 2, WP

0319

Equipment Condition

Vehicle parked and engine shut down.

(TM

9-2320-272-10)

TROUBLESHOOTING PROCEDURE

ENGINE AND VEHICLE ELECTRICAL SYSTEMS MALFUNCTIONING

NOTE

Conduct these malfunction tests if engine and vehicle electrical systems are malfunctioning.

This procedure will check the protective control box function.

STEP

1.

ARE VEHICLE GROUND STRAPS SECURELY FASTENED?

a.

Ensure ground straps are securely fastened.

b.

Ensure no paint is under starwashers.

CONDITION/INDICATION

ARE VEHICLE GROUND STRAPS SECURELY FASTENED?

DECISION

NO - Remove paint and secure ground strap. Go to Step (3) to verify problem is solved.

YES - Go to Step (2).

TM 9-2320-272-23-1

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