Navistar International DT 466 Diagnostic/Troubleshooting Manual page 350

346 7 ELECTRONIC CONTROL SYSTEMS DIAGNOSTICS
NOTE: Complete all pin-point diagnostics (ECM to valve cover gasket connector) before removing
valve cover for under-valve-cover diagnostics.
• Turn the ignition switch to OFF before disconnecting engine wiring harness connectors from components.
See truck Chassis Electrical Circuit Diagram Manual for circuit numbers, connector and fuse locations.
•
Harness Resistance Check – UVC Connector to ECM Chassis Ground (Turn the ignition switch to OFF.
Disconnect chassis connector 9260
Test Point Spec
1 to Pin A (9260) < 5 Ω
2 to Pin A (9260) > 1 kΩ
Harness Resistance Check – UVC Connector to Chassis Ground (Turn the ignition switch to OFF.
Disconnect chassis connector 9260
Use disconnected negative battery cable for ground test point.)
1 to gnd cable > 500 Ω
2 to gnd cable
> 1 kΩ
Harness Resistance Check – Valve Cover Gasket Connector to UVC Connector (Connect VC Gasket
Breakout Harness to valve cover gasket only.)
A to 1 < 5 Ω
C to 2 < 5 Ω
Solenoid Resistance Check – Brake Shut-off Valve (Measure across terminals of solenoid.)
2 to 1 10 Ω ± 2 Ω If not to specification, replace brake shut-off valve.
1
Connector 9260 is a 2-wire connector usually located in the battery box. Pin A is the ground connection for the ECM
and IDM. See truck Chassis Electrical Circuit Diagram Manual for complete chassis side ECM and IDM ground circuit
information.
Read all safety instructions in the "Safety Information" section of this manual before doing any procedures.
1
.)
Comment
If > 5 Ω, check for an open circuit.
If < 1 kΩ, check for short to ground within wiring harness.
1
. Disconnect negative battery cable. Disconnect harness from valve.
If < 500 Ω, check for short to ground.
If < 1 kΩ, check for short to ground.
If > 5 Ω, check for open in actuator ground.
If > 5 Ω, check for open in control wire.
EGES-270-1
Follow all warnings, cautions, and notes.
© August 2008 Navistar, Inc.