Navistar INTERNATIONAL DT 466 User Manual

7 ELECTRONIC CONTROL SYSTEMS DIAGNOSTICS 385
85 to gnd 0.06 V to 2 V
If > 2 V is present, check for open circuit between Pin X3–5 to Pin 85 on
relay or V
IGN
circuit. See truck Chassis Electrical Circuit Diagram Manual
for relay and fuse locations.
87 to gnd 12 V ±1.5 V
Continuous voltage. If previous test points are in spec and no voltage is
present, replace relay.
CAUTION: To avoid engine damage, turn the ignition switch to OFF before removing main power relay or any
ECM connector supplying power to the ECM. Failure to turn the ignition switch to OFF will cause a voltage
spike and damage to electrical components.
Voltage Checks at ECM – Key-On Engine-Off (Follow tests in
order. Check with breakout box connected
between chassis harness and ECM. Inspect for bent pins an
d corrosion.)
Test Point
Spec Comment
X3–3 to gnd 12 V ± 1.5 V
Power from ignition switch to ECM. If no voltage, see truck Chassis
Electrical Circuit Diagram Manual for relay and fuse locations.
X3–6 to gnd 0 V to 0.25 V
Ground – voltage reading indicates poor ground
to battery. If voltage
is present check for open or high resistance be
tween battery (–) and
ECM pins.
X3–7 to gnd 0 V to 0.25 V
Ground – voltage reading indicates poor ground to battery. If voltage
is present check for open or high resistance between battery (–) and
ECM pins.
X3–5 to gnd 0.06 V to 2 V
ECM grounds relay through internal transistor. If > 2 V is present, replace
ECM.
X4–1 to gnd 12 V ± 1.5 V
Power from relay to ECM. If no voltag
e, check for open between X4–1
and87onECMrelay. SeetruckChassi
s Electrical Circuit Diagram
Manual for relay and fuse location
s.
X4–2 to gnd 12 V ± 1.5 V
Power from relay to ECM. If no voltage, check for open between X4–2
and87onECMrelay. SeetruckChassis Electrical Circuit Diagram
Manual for relay and fuse locations.
CAUTION: To avoid engine damage, turn the ignition switch to OFF before removing main power relay or any
ECM connector supplying power to the ECM. Failure to turn the ignition switch to OFF will cause a voltage
spike and damage to electrical components.
Harness Resistance Check
s–ECMtoMainPowerRelay(Turn the ignition switch to OFF. Inspect for bent
pins or corrosion. Conne
ct relay breakout harness and breakout box to X3 and X4 chassis harness only.)
Test Point
Spec Comment
X3–5 to 85 (ECM relay) < 5 Ω If > 5 Ω, check connections for open between ECM and relay.
See truck Chassis Electrical Circuit Diagram Manual for relay and
fuse locations.
X4–1 to 87 (ECM relay
)
<5Ω If > 5 Ω, check connec
tions for open between ECM and relay.
See truck Chassis E
lectrical Circuit Diagram Manual for relay and
fuse locations.
X4–2 to 87 (ECM relay) < 5 Ω If > 5 Ω, check connections for open between ECM and relay.
See truck Chassis Electrical Circuit Diagram Manual for relay and
fuse locations.
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.

Navistar INTERNATIONAL DT 466 Specifications

General

Brand	Navistar
Model	INTERNATIONAL DT 466
Category	Engine
Language	English