S2118000001RevB

Case Number: S2118000001 REV. B
Release Date: July 2022
Symptom/Vehicle Issue: Malfunction Indicator Lamp (MIL) Illumination. Diagnostic
Trouble Code (DTC) P0471 – Exhaust Pressure Sensor 1 Performance, Set.
Discussion: A small number of customers may experience a MIL illumination. Upon
further investigation, a technician may find DTC P0471 set in the Powertrain Control
Module (PCM).
In addition to P0471, you may also have one or more of the following DTCs set:
•
•
•
•
P1451 – Diesel Particulate Filter System Performance
P2463 – Diesel Particulate Filter Restriction
P242F – Diesel Particulate Filter Restriction, Ash Accumulation
P0506 – Idle Control System, RPM Lower Than Expected
DTC P0471 may be caused by back pressure in the exhaust due to plugging up of the
Aftertreatment system. If you are diagnosing a vehicle with P0471 set, please inspect
for, and repair, any possible restrictions in the exhaust system that may be leading to
this DTC to set.
NOTE: Do not replace the Exhaust Manifold Pressure (EMP) sensor for this DTC
if the exhaust system is found to be restricted. The P0471 setting will not lead to
the exhaust system becoming restricted.
If you receive a vehicle with this concern, please perform the following.
1. Prior to clearing any DTCs, obtain a current Freeze Frame report via wiTECH.
2. Email the report to the following email address ([email protected]). In the
email subject, please put “Freeze Frame Report for P0471. This is for information
gathering purposes to better understand what may be leading to the DTC setting.
This document does not authorize warranty repairs. This communication documents a record of past experiences. STAR Online
does not provide any conclusions about what is wrong with the vehicle. Rather, it captures all previous cases known that appear
to be similar or related to the vehicle symptom / condition. You are the expert, and you are responsible for deciding on the
appropriate course of action.
Contact STAR Center, or your Technical Assistance Center Via TechCONNECT or eCONTACT ticket if no
solution is found
FCA US LLC
Version 4.3 10/28/2020
3. Inspect the exhaust system for restrictions (e.g. DOC/DPF face plugging).
4. If the exhaust is found restricted. Inspect the following areas for the cause of the
restriction.
a. Restricted air intake
b. Restricted EGR systems,
c. Fuel system concerns causing over fueling, etc.
5. Inspect the Charge Air Cooler (CAC) hoses for loose connections/clamps, splits,
and other damage which can also cause the exhaust system to plug up. Please
see (Figures 1, 2, and 3).
Figure 1
Figure 2
This document does not authorize warranty repairs. This communication documents a record of past experiences. STAR Online
does not provide any conclusions about what is wrong with the vehicle. Rather, it captures all previous cases known that appear
to be similar or related to the vehicle symptom / condition. You are the expert, and you are responsible for deciding on the
appropriate course of action.
Contact STAR Center, or your Technical Assistance Center Via TechCONNECT or eCONTACT ticket if no
solution is found
FCA US LLC
Version 4.3 10/28/2020
Figure 3
1.
CAC Hose Clamp
6. Repair the cause of the exhaust restriction prior to replacing any of the exhaust
components.
This document does not authorize warranty repairs. This communication documents a record of past experiences. STAR Online
does not provide any conclusions about what is wrong with the vehicle. Rather, it captures all previous cases known that appear
to be similar or related to the vehicle symptom / condition. You are the expert, and you are responsible for deciding on the
appropriate course of action.
Contact STAR Center, or your Technical Assistance Center Via TechCONNECT or eCONTACT ticket if no
solution is found
FCA US LLC
Version 4.3 10/28/2020