Navistar MaxxForce DT Diagnostic Manual page 104

DIAGNOSTIC MANUAL
Step
8C Verify aftertreatment system is free of restrictions. Using
EST, use the playback feature and graph the following
signal values from Lug Down Test:
Signal Values:
• Engine Speed
• Turbocharger 1 Turbine Outlet Pressure (TC1TOP)
Compare snapshot to Graph 4 and associated Graph
Analysis page 126.
Is TC1TOP signal operating as per Graph 4 Graph
Analysis?
Step
8D Check for an Intake Manifold Pressure (IMP) issue. Use the
playback feature in ServiceMaxx™, and graph the following
signal values from Lug Down Test:
Signal Values:
• Engine Speed
• Intake Manifold Pressure (IMP)
• Accelerator Pedal Position 1 (APP1)
• Vehicle Speed
Compare snapshot to Graph 5 and associated Graph
Analysis page 127.
Is IMP operating as per Graph 5 Graph Analysis?
100
Action
Action
https://www.truck-manuals.net/
Decision
Yes: Go to step 8D
No: Repair TC1TOP issue (See
Electronic Control Systems Diagnostics
in Engine Diagnostic Manual). After
repairs are complete, retest for original
problem.
Decision
Yes: Go to step 9
No: Diagnose and repair IMP issue
(See Performance Diagnostics section
in Engine Diagnostic Manual). After
repairs are complete, retest for original
problem.