Navistar MaxxForce DT Diagnostic Manual page 17

Step
5 Determine if DPF, DOC, and PDOC are reusable see the DPF and DOC
reuse guidelines page 159.
Based on DPF and DOC Re-Use Guidelines, are the DPF, DOC, and
PDOC reusable?
Step
6 Determine root cause of exhaust system contamination. (See Engine
Symptoms Diagnostics section in Engine Diagnostic Manual.)
Action
Action
https://www.truck-manuals.net/
DIAGNOSTIC MANUAL
Decision
Yes: Install
removed
aftertreatment
system
components, and
go to step 6.
No: Replace
failed
component(s).
After repairs are
complete, go to
step 6.
Decision
After repairs are
complete, go to
step 7.
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