DIAGNOSTICMANUAL
3.2.SYMPTOM1(MEDIUMDUTY):FREQUENTPARKEDREGENSWITHNOACTIVE
FAULTCODES(MORETHANONEPARKEDREGENPERDAY)
NOTE–Beforebeginningthefollowingstep-baseddiagnostics,performallvehicleoperationalchecks
page5.
NOTE–SPN3719FMI15maybeinactivewhenafrequentregenconcernispresent.
NOTE–SPN3936FMI8canbeactiveforthissymptom.
Step
ActionDecision
1
CheckforafailedAirManagementSystem(AMS)actuator.
1.UsingElectronicServiceT ool(EST)withServiceMaxx™
software,gotoT ests>LoadTestSpecicSessionandverify
LoadTestSpecicSessionisunchecked.
2.GotoSessions>Performanceandselecttherecordsnapshot
iconfromthetoolbar.
3.GotoT ests>KOERT ests>AirManagementT est.
WhenAirManagementT estiscomplete,stoprecording.Usetheplayback
featureinServiceMaxx™,andgraphthefollowingsignalvalues:
SignalValues:
•MassAirFlow(MAF)MeanValue(MMV)
•IntakeManifoldPressure(IMP)
•ExhaustGasRecirculation(EGR)valveposition
DoessnapshotmatchGraph1orGraph2page51?
Graph1:Goto
step2A
Graph2:
Diagnoseand
repairfailed
actuator(See
Performance
Diagnostics
sectioninEngine
Diagnostic
Manual).After
repairsare
complete,retest
fororiginal
problem.
8
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