VOLTAGE TEST -726280491

TM 9-2320-364-20-1

Remove all jewelry such as rings, dog tags, bracelets, etc. If jewelry or tools contact positive electrical

circuits, a direct short may result. Damage to equipment, injury or death to personnel may occur.

Allow engine to cool before performing troubleshooting maintenance. If necessary use insulated pads

and gloves. Hot engine components will burn and cause personnel injury.

DDEC ECM connector terminals are easily damaged.

Use care when connecting and disconnecting connectors.

VOLTAGE TEST

(1) Set multimeter select switch to

volts dc.

(2) Connect positive (+) multimeter lead

to vehicle harness connector MC18,

terminal B3.

(3) Connect negative (- ) multimeter lead

to a known good ground.

(4) Turn ON ENGINE switch

(TM 9-2320-364-10).

(5) Are there 10 to 14 vdc present

between wire 439 at vehicle harness

connector MC18, terminal B3 and a

known good ground?

(a) If there are less than 10 vdc

present, turn OFF ENGINE switch

and repair wire 439 (see

schematic Fig 2-1) or notify DS

Maintenance.

(b) If more than 10 vdc are present,

perform Step (6) and (7) below

and go to Step 6 of this Fault.

(6) Turn OFF ENGINE switch.

(7) Connect vehicle harness connector

MC18 and tighten screw.

VOLTAGE TEST

(1) Remove two mounting screws and

heat shield from DDEC ECM.

(2) Disconnect power harness connector

MC17 at DDEC ECM with connector

remover.

(3) Connect positive (+) multimeter lead

to power harness connector MC17,

terminals A, B, E and F, one at a time.

(4) Connect negative (- ) multimeter lead

to a known good ground.

(5) Turn ON ENGINE switch

(TM 9-2320-364-10).

(6) Are 10 to 14 vdc present between

wires 241 and 240 at power harness

connector MC17, terminals A, B, E

and F and a known good ground?

(a) If there are less than 10 vdc

present, turn OFF ENGINE switch

and repair wires 241 and/or 240

(see schematic Fig 2-3) or notify

DS Maintenance.

(b) If more than 10 vdc are present,

turn OFF ENGINE switch and go

to Step 7 of this Fault.

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