Service bulletin S2121000008

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

The communication, as NHTSA indexes it (as of 2026-10-19)
Type	Service bulletin
NHTSA id	10223243
Published by NHTSA	2022-10-17
Manufacturer's number	S2121000008
Manufacturer's date	2021-05-03
NHTSA component	EXTERIOR LIGHTING

NHTSA's summary

Malfunction Indicator Lamp (MIL) Illumination. Diagnostic Trouble Codes (DTCs) P0756 ? UD Solenoid Circuit, and/or P0755 ? 2C Solenoid Circuit, Set.

The document

The document is the manufacturer's. This site does not hold it. NHTSA files a document at one of these two addresses; we have not asked NHTSA which.

Components

Lighting

Trouble codes named

P0755, P0756

Vehicles listed
RAM 2500	2019, 2020, 2021
RAM 3500	2019, 2020, 2021

Listing a model year does not mean every vehicle of it is concerned: the document says which.

Recalls for the same vehicles and component
2019258	2019-05-31. Lights And Instruments

A recall listed here may apply to some of the same vehicles. Only the manufacturer can say whether it applies to one vehicle.

Other bulletins for the same vehicles and component
1800824	2024-03-18. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs) have been set: P0506-00 - Idle Control System RPM - Lower Than Expected.P0607-00 - ECU Internal Performance. P20E8-00 - Reductant Pressure Too Low. P0301-00 - Cylinder 1 Misfire. P0302-00 - Cylinder 2 Misfire. P0303-00 - Cylinder 3 Misfire. P0304-00 - Cylinder 4 Misfire. P0305-00 - Cylinder 5 Misfire. P0306-00 - Cylinder 6 Misfire. P0299-00 - Turbocharger Underboost. P1D73-00 - AGS Performance. P0626 - Generator Field Control Circuit High. P218F - Reductant No Flow Detected. P2002 - Diesel Particulate Filter Efficiency Below Threshold. P24A5 - EGR Cooler Bypass Bank 1 Control Stuck. P0191 - Fuel Rail Pressure Sensor Circuit Performance. P0461 - Fuel Level Sensor 1 Performance. P0401 - EGR System Performance. P20EE - SCR NOx Catalyst Efficiency Below Threshold - Bank 1. P061A - Level 2 Torque Performance. P061B - Internal Control Module Torque Calculation Performance. P061E - Internal Control Module Brake Signal Performance. P062C - ETC Level 2 MPH Performance. P0106 - Manifold Absolute Pressure Sensor Performance (In extreme cold ambient temperatures). P0116 - Engine Coolant Temperature Sensor Performance. P0420 - Catalyst System Efficiency Bank 1. P1507 - Crankcase Filter Restriction. P203F - Reductant Level Too Low. P226C - Turbocharger Boost Control ?A? Slow Response (In extreme cold ambient temperatures). P2579 - Turbocharger Speed Sensor Circuit. U0101 - Lost Communication with TCM. U02A3 - Lost of Communication with PM Sensor. U3017 - Control Module Timer/Clock Performance. Customers may also experience one or more of the following Power
1800724	2024-03-18. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find one or more of the following Diagnostic Trouble Codes (DTCs) have been set: P0506-00 - Idle Control System RPM - Lower Than Expected. P0607-00 - ECU Internal Performance. P20E8-00 - Reductant Pressure Too Low. P0301-00 - Cylinder 1 Misfire. P0302-00 - Cylinder 2 Misfire. P0303-00 - Cylinder 3 Misfire. P0304-00 - Cylinder 4 Misfire. P0305-00 - Cylinder 5 Misfire. P0306-00 - Cylinder 6 Misfire. P0299-00 - Turbocharger Underboost. P1D73-00 - AGS Performance. P0626 - Generator Field Control Circuit High. P218F - Reductant No Flow Detected. P2002 - Diesel Particulate Filter Efficiency Below Threshold. P24A5 - EGR Cooler Bypass Bank 1 Control Stuck. P0191 - Fuel Rail Pressure Sensor Circuit Performance. P0461 - Fuel Level Sensor 1 Performance. P0401 - EGR System Performance. P20EE - SCR NOx Catalyst Efficiency Below Threshold - Bank 1. P061A - Level 2 Torque Performance. P061B - Internal Control Module Torque Calculation Performance. P061E - Internal Control Module Brake Signal Performance. P062C - ETC Level 2 MPH Performance. P0106 - Manifold Absolute Pressure Sensor Performance (In extreme cold ambient temperatures). P0116 - Engine Coolant Temperature Sensor Performance. P0420 - Catalyst System Efficiency Bank 1. P1507 - Crankcase Filter Restriction. P203F - Reductant Level Too Low. P226C - Turbocharger Boost Control ?A? Slow Response (In extreme cold ambient temperatures). P2579 - Turbocharger Speed Sensor Circuit. U0101 - Lost Communication with TCM. U02A3 - Lost of Communication with PM Sensor. U3017 - Control Module Timer/Clock Performance.
1806823	2023-07-31. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that one or more of the following Diagnostic Trouble Codes (DTCs) have been set: ? P1404 - EGR Position Sensor Rationality Closed. ? P2457 - Exhaust Gas Recirculation Cooling System Performance. NOTE: P1404 - EGR Position Sensor Rationality Closed DTC can be erroneously set when P2457 -Exhaust Gas Recirculation Cooling System Performance DTC is set. In addition, the customer may notice one or more of the following conditions: ? Power Take Off (PTO) disable to high engine oil temperature (DD DP with DF3 Only). ? In PTO mode, transmission gear engagement is abrupt and idle speed is high when transitioning From Park To Drive/Reverse Gear. This bulletin involves reprogramming the PCM with the latest available software.
S1625000003 Rev.	2023-02-13. Service bulletin. Malfunction Indicator Lamp (MIL) Illumination. NOx Sensor Diagnostic Trouble Codes (DTCs) Diagnosis Information.
9100096	2023-01-17. Service bulletin. Base Headlamp Bright, Base Headlamp Black
S2118000001RevB	2023-01-17. Service bulletin. Malfunction Indicator Lamp (MIL) Illumination. Diagnostic Trouble Code (DTC) P0471 ? Exhaust Pressure Sensor 1 Performance, Set.
S2118000012	2023-01-17. Service bulletin. Malfunction Indicator Lamp (MIL) Illumination. Diagnostic Trouble Code (DTC) P0607 ? ECU Internal Performance, Set.
S2025000007	2023-01-17. Service bulletin. Malfunction Indicator Lamp (MIL) Illumination. Diagnostic Trouble Code (DTC) P218F ? Reductant No Flow Detected set.
0900421	2023-01-17. Service bulletin. Oil Control Valve Connector Not Seated This bulletin involves inspecting the oil control valve connector and possibly seating the connector. Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find the following Diagnostic Trouble Code (DTC) has been set: P0013 - Bank 1 Camshaft 2 Position Actuator Circuit Open.
18-099-22 REV. A	2023-01-17. Service bulletin. Diesel Fuel Pump Failure and System Contamination Customers may experience a Malfunction Indicator Lamp (MIL) illumination. Upon further investigation the technician may find that one or more of the following Diagnostic Trouble Codes (DTCs) have been set: ? P0087-00 - Fuel Rail Pressure Too Low. ? P008A-00 - Low Pressure Fuel System Pressure - Too Low. ? P0201-00 - Fuel Injector 1 Circuit/Open. ? P0202-00 - Fuel Injector 2 Circuit/Open. ? P0203-00 - Fuel Injector 3 Circuit/Open. ? P0204-00 - Fuel Injector 4 Circuit/Open. ? P0205-00 - Fuel Injector 5 Circuit/Open. ? P0206-00 - Fuel Injector 6 Circuit/Open. The customer may also notice the following: ? Engine will not start. This TSB is being replaced by recall Y78, please review Y78 for further details.