RESISTANCE TEST -726280229

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) Disconnect DDR cable from DDL

connector.

(2) Read resistance between wire 435

at DDL connector MC13, terminal A

and a known good ground?

(a) If more than 3,000 ohms are

present, repair wire 435 (see

schematic Fig 2-1) or notify DS

Maintenance.

(b) If less than 3,000 ohms are

present, go to Step (3) below.

(3) Loosen screw and disconnect vehicle

harness connector MC18 from

DDEC ECM.

(4) Are there more than 3,000 ohms

present on the following wires:

wire 451 between DDL connector

MC13, terminal M and vehicle

harness connector MC18,

terminal E1.

wire 900 between DDL connector

MC13, terminal J and vehicle

harness connector MC18,

terminal C2.

wire 901 between DDL connector

MC13, terminal K and vehicle

harness connector MC18,

terminal C1.

(a) If more than 3,000 ohms are

present, repair wires (see

schematic Fig 2-1) or notify DS

Maintenance.

(b) If less than 3,000 ohms are

present, wires 451, 900 and/or

901 are OK.

(5) Connect vehicle harness connector

MC18 to DDEC ECM and tighten

screw.

2-159