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 394 of 1313

ENGINE CRANKS BUT WILL NOT START IN COLD WEATHER (FUEL SYSTEM OPERATING PROPERLY) -

Continued

c.

Make sure battery switch is in ON position.

d.

Connect red lead to circuit 570 ether start switch connector.

e.

Connect black lead to good ground.

f.

Multimeter will display volts DC.

g.

Depress ether start switch.

NOTE

If battery voltage is present, circuit 570 wire is faulty.

h.

Meter reading should be greater than 18 VDC.

CONDITION/INDICATION

DOES CIRCUIT 570 WIRE CONDUCT BATTERY VOLTAGE TO FUEL PRESSURE SWITCH?

DECISION

YES - Go to Step (6).

NO - Repair circuit 570 wire to fuel pressure switch (Volume 3, WP

0352). Go to Step (10) to verify problem is

solved.

TM 9-2320-272-23-1

0021

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