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 392 of 1313

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

Continued

c.

Connect red lead to circuit 570 wire.

d.

Connect black lead to good ground.

e.

Multimeter will display volts DC.

f.

Crank engine and depress ether start switch.

NOTE

If battery voltage is present, fuel pressure switch is faulty.

g.

Meter reading should be greater than 18 VDC.

CONDITION/INDICATION

DOES FUEL PRESSURE SWITCH OPERATE PROPERLY?

DECISION

YES - Go to Step (5).

NO - Replace fuel pressure switch (Volume 2, WP

0337). Go to Step (10) to verify problem is solved.

TM 9-2320-272-23-1

0021

0021-7