Pin-Point Diagnostics; Connector Voltage Checks To Ground; Connector Resistance Checks To Ecm Chassis Ground - Navistar International DT 466 Diagnostic/Troubleshooting Manual

290 7 ELECTRONIC CONTROL SYSTEMS DIAGNOSTICS

Pin-Point Diagnostics

Some Pin-Point Diagnostic
MasterDiagnostics® Output State Tests.
help, see "Diagnostic Software Operation" in Section
3 (page 68) for procedure to run the Low and High
Output State Tests.

Connector Voltage Checks to Ground

Figure 370 V check
REF
Procedure
1. Turn the ignition switch to ON.
2. Connect breakout harness to the harness only.
3. Measure voltage at each pin with a DMM.
4. Compare sensor or actuator voltage readings with
the expected voltages. See Circuit Diagnostics in
this section for circuit specifications.
If a breakout harness is not available, use the
correct tool from Terminal Test Adapter Kit. Do not
directly probe the connector pins with the DMM
leads. For a circuit with an expected voltage, this
test will verify circuit integrity.
5. Turn the ignition to OFF.
For circuits without an expected voltage, this test will
determine if that circuit is shorted or incorrectly wired
to ground, V , B+ or other voltage sources.
REF
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
Connector Resistance Checks to ECM Chassis
Ground
tests use the
For
Figure 371 Resistance check to ECM chassis
ground
Procedure
NOTE: The truck Chassis Electrical Circuit Diagram
Manual should always be used for chassis ground
circuit information.
1. Disconnect chassis connector 9260.
2. Connect breakout harness to harness only.
3. Use breakout harness to measure resistance from
EGES-270-1
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.
NOTE: Connector 9260 is a 2-wire connector
usually located in the battery box. Pin A is the
chassis ground connection for the ECM and IDM.
See truck Chassis Electrical Circuit Diagram
Manual for complete chassis side ECM and IDM
ground circuit information.
the lead of the breakout harness to the connector
9260 Pin A.
See Circuit Diagnostics in this section for circuit
specifications.
Sensor signal ground circuits should measure
less than 5 ohms.
V and signal circuits should measure more than
REF
1 k ohm.
The control side of an actuator will measure more
than 1 k ohms, but the expected voltage for the
other side of the actuator circuit will measure the