RESISTANCE TEST -726280327

TM 9-2320-364-20-1

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

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

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.

DDEC ECM connector terminals are easily damaged. Use care when connecting and disconnecting

connectors.

RESISTANCE TEST

(1) Loosen screw and disconnect engine

harness connector from DDEC ECM.

(2) Read resistance between wires 472

and 452 at engine harness connector,

terminals R3 and Y2.

(a) If there are less than 10,000 ohms

present, repair wires 472 and/or

452 (see schematic Fig 2-2) or

notify DS Maintenance.

(b) If there are more than 10,000

ohms present, wires 472 and 452,

go to Step (3) below.

(3) Read resistance between wire 472

on FTS connector terminal B and a

known good ground.

(a) If there are less than 10,000 ohms

present, repair wire 472 (see

schematic Fig 2-2) or notify DS

Maintenance.

(b) If there are more than 10,000

ohms present wire 472 is OK.

VISUAL INSPECTION

(1) Check terminals at engine harness

connector (DDEC ECM and harness

side) for damage; bent, corroded and

unseated pins or terminals.

(a) If harness connector is damaged,

repair connector (Para 7-101) and

perform Steps (2) through (4)

below.

(b) If DDEC ECM connector is

damaged, replace DDEC ECM

(Para 7-56).

connectors are OK, replace

DDEC ECM (Para 7-56).

(2) Connect engine harness connector

to DDEC ECM and tighten screw.

(3) Install DDEC ECM (Para 7-56).

(4) Close top engine access cover.