3–5
T-378
3.6 Sensors
The temperature sensors monitor unit operation and report back to the ECM.
3.6.1
Exhaust Inlet Temperature Sensor (ESEIT)
The Exhaust Inlet Temperature Sensor (ESEIT),
, monitors temperature entering the DOC. It is located
just before the Doser and DOC. This temperature is directly dependent upon engine load and determines which
type of regeneration is needed. When upstream temperatures are high enough (during high engine load), passive
regeneration will occur. Refer to
for a description of how regeneration works.
Figure 3.9 ESEIT
3.6.2
Filter Inlet Temperature Sensor (ESFIT)
The Filter Inlet Temperature Sensor (ESFIT),
, monitors exhaust temperature entering the DPF. It is
located after the DOC and before the DPF. This temperature data is utilized to control and maintain regeneration
temperature at approximately 1112 °F (600°C). This temperature is maintained by injecting fuel into the system
(active regeneration), or in some cases, using the ACV to restrict engine air intake (active-assist regeneration).
Figure 3.10 ESFIT
