DIAGNOSTICMANUAL
Actions:
1.AfterDOCreachesoperatingtemperatureandstabilizes(seecallout3,graph7),verifyDPFOT
signalvalueisnot122°F(50°C)higherthanDOCOTsignalvalue.Inthisgraph,DPFOTsignal
valueis122°F(50°C)higherthanDOCOTindicatinginvertedexhaustgastemperatures.
2.VerifyDieselOxidationCatalystInletTemperature(DOCIT)signalvalueisbetween550°F(287°C)
to800°F(427°C).
NOTE–ItisnormaltoseeDieselOxidationCatalystInletTemperatureDOCIT,DOCOT ,andDPFOTsignal
valuestouctuateatthebeginningandendoftheOBFCT.
NOTE–SPN4766FMI10(DOCEfciency)maybeactivewhenexhaustgastemperaturesareinverted.
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