Navistar MaxxForce DT Diagnostic Manual page 136

DIAGNOSTIC MANUAL
Actions:
1. After DOC reaches operating temperature and stabilizes (see callout 3, graph 7), verify DPFOT
signal value is not 122°F (50°C) higher than DOCOT signal value. In this graph, DPFOT signal
value is 122°F (50°C) higher than DOCOT indicating inverted exhaust gas temperatures.
2. Verify Diesel Oxidation Catalyst Inlet Temperature (DOCIT) signal value is between 550°F (287°C)
to 800°F (427°C).
NOTE – It is normal to see Diesel Oxidation Catalyst Inlet Temperature DOCIT, DOCOT, and DPFOT signal
values to fluctuate at the beginning and end of the OBFCT.
NOTE – SPN 4766 FMI 10 (DOC Efficiency) may be active when exhaust gas temperatures are inverted.
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