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 968 of 1313

FIELD MAINTENANCE

HEATER WILL NOT OPERATE IN LOW OR HIGH POSITION

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.)

Volume 2, WP

0307

Volume 3, WP

0352

Volume 4, WP

0747

Equipment Condition

Vehicle parked and engine shut down.

(TM

9-2320-272-10)

TROUBLESHOOTING PROCEDURE

HEATER WILL NOT OPERATE IN LOW OR HIGH POSITION

NOTE

Conduct these malfunction tests if heater will not operate in low or high position. This

procedure will check for faulty heater switch, faulty wiring, or faulty heater.

TM 9-2320-272-23-1

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