DDR TEST -726280265

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 personnel injury.

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.

DDR TEST

(1) Remove ten screws, sunshield and

tilt instrument panel.

(2) Disconnect vernier control harness

connector MC38.

(3) Turn ON ENGINE switch

(TM 9-2320-364-10).

(4) Select MODE 01 (ACTIVE CODES)

on DDR and read codes.

(a) If code 12 is only code

displayed, turn OFF ENGINE

switch and go to Step 5 of this

Fault.

(b) If other codes are displayed, turn

OFF ENGINE switch and go to

Step 3 of this Fault.

Use jumperwire only between terminals

indicated. Failure to comply may result in

damage to DDEC components or wiring.

DDEC ECM connector terminals are easily

damaged. Use care when connecting and

disconnecting connectors.

RESISTANCE TEST

(1) Place jumperwire across terminals

A and B of vernier control harness

connector MC38.

(2) Loosen screw and disconnect vehicle

harness connector MC18 at

DDEC ECM.

(3) Turn ON ENGINE switch

(TM 9-2320-364-10).

(4) Turn on crane power switch and latch

high idle.

(5) Read resistance between terminals

C3 and D1 on the vehicle harness

connector MC18.

(a) If more than 5 ohms are present,

perform Steps (6) and (7) below

and remove jumperwire and repair

wire 952 (see schematic Fig 2-1)

or notify DS Maintenance.

(b) If less than 5 ohms are present,

wire 952 is OK, remove

jumperwire and perform Steps

(6) and (7) below.

(6) Turn OFF ENGINE switch and crane

power switch.

(7) Connect vehicle harness connector

MC18 and tighten screw.

2-195