420 7 ELECTRONIC CONTROL SYSTEMS DIAGNOSTICS
WARNING: To avoid serious personal injury, possible death, or damage to the engine or vehicle,
always disconnect main negative battery cable first. Always connect the main negative battery cable
last.
EGR Actuator Harness Connector Resistance Checks to Chassis Ground (Turn the ignition switch
to OFF. Disconnect chassis connector 9260
1
. Disconnect harness from actuator. Disconnect negative
battery cable. Connect breakout harness to engine harness only. Use disconnected negative battery
cable for ground test point.)
1tognd
>1kΩ If < 1 kΩ, short to ground exists.
2tognd
>1kΩ If < 1 kΩ, short to ground exists.
3tognd
>1kΩ If < 1 kΩ, short to ground exists.
4tognd
>1kΩ If < 1 kΩ, short to ground exists.
5tognd
>1kΩ If < 1 kΩ, short to ground exists. Specification is based on 4300
chassis. For other applications, see Chassis Electrical Circuit Dia gram
Manual for complete chassis ground circuit information.
6tognd
>1kΩ If < 1 kΩ, short to ground exists.
7tognd
>1kΩ If < 1 kΩ, short to ground exists.
8tognd
>1kΩ If < 1 kΩ, short to ground exists.
1
Connector 9260 is a 2-wire con nector usually locate d in the battery box. Pin A is the ground connection fo r th e E CM
and IDM. See truck Chassis Electrical Ci
rcuit Diagr am Manual for complete chassis side ECM and IDM groun d circuit
information.
WARNING: To avoid serious personal injury, possible death, or damage to the engine or vehicle,
make sure the transmission is in neutral, parking brake is set, and wheels are blocked before doing
service bay diagnostics on engine or vehicle.
CAUTION: To avoid engine damage, use utmost care when:
1. Disconnecting harness from EGR actuator or EGR drive module.
2. Inserting Terminal Test Adapter probe into connector to test for specifications.
3. Connecting harness to EGR actuator or EGR drive m odule.
Failure to use care when disconnecting, testing, or connecting components may result in damaged or bent
connector pins.
EGR Drive Module Connector Voltage Checks (Disconnect harness from the EGR drive module. Turn the
ignition switch to ON.)
Test Point
Spec Comment
1tognd 9Vto16V
If not in spec, check for an open, short to ground, or short to voltage
source.
2tognd 0V
If not in spec, check for a short to voltage source.
3tognd 1Vto4V
Digital signal. See “ECM
/ IDM Communications” (page 373).
EGES-270-1
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.