Service bulletin 21-046-25

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	11025504
Published by NHTSA	2025-11-13
Manufacturer's number	21-046-25
Manufacturer's date	2025-11-08
NHTSA component	POWER TRAIN

NHTSA's summary

Flash: Transmission Control Module (TCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0827-00 - Up and Down Shift Switch Circuit Low. ● P0826-00 - Up and Down Shift Switch Circuit. ● P085F-00 - Up and Down Shift Switch Circuit Range/Performance. The customer may describe one or more of the following: ● Vehicle stuck in default gear, and possibly stranded for many minutes. ● Rough or bumpy 2-3 power on upshifts and/or 3-2 coast down shifts. ● Vehicle enters into limp home mode. In addition, the following software enhancement is available: ● Decreased sensitivity to DTCs P1D8A and P1D8 This bulletin involves reprogramming the TCM with the latest available software.

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

Transmission and driveline

Trouble codes named

P0826, P0827, P085F, P1D8A

Vehicles listed
RAM 2500	2026

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

Recalls for the same vehicles and component
2026225	2026-05-07. Powertrain
26V288000	2026-05-07. POWER TRAIN:AUTOMATIC TRANSMISSION:CONTROL MODULE (TCM/PCM/TECM)

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
114739	2026-09-30. Service bulletin. TRANSMISSION KIT - WITH TORQUE CONVERTER
08-302-26	2026-08-06. Service bulletin. Flash: Electronic Shift Module (ESM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set the following Diagnostic Trouble Code (DTC): ● U1057-00 - High Speed Fd-Can3 Communication Bus Performance. Customers may also comment on the following: ● If the vehicle has a low or drained battery and requires a jump start, once jump started, the vehicle will not shift out of Park. This bulletin involves reprogramming the ESM with the latest available software.
18-067-26 REV. A	2026-07-23. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0088-00 - Fuel Rail Pressure Too High - Bank 1. ● P208B-00 - Reductant Pump 1 Control Performance. This bulletin involves inspecting and possibly reprogramming the PCM with the latest available software.
S2523000088 REV.B	2026-07-18. Service bulletin. Vehicle Shifter Will Not Shift Out Of Park.
18-067-26	2026-07-18. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0088-00 - Fuel Rail Pressure Too High - Bank 1. ● P208B-00 - Reductant Pump 1 Control Performance. ● P2540-00 - Low Pressure Fuel System Sensor Circuit Range/Performance. ● P0506-00 - Idle Control System RPM - Lower Than Expected. ● P20CF-00 - Exhaust Aftertreatment Fuel Injector "A" Stuck Open. ● P20DB-00 - Exhaust Aftertreatment Fuel Supply Control Stuck Open. ● P040B-00 - EGR Temperature Sensor 1 Circuit Performance. ● U0109-00 - Lost Communication With Fuel Pump Control Module. ● P1451-00 - Diesel Particulate Filter System Performance. ● P2463-00 - Diesel Particulate Filter Restriction - Soot Accumulation Bank 1. ● P1191-00-Inlet Air Temperature Sensor Rational/Performance. ● P242F-00-Diesel Particulate Filter Restriction - Ash Accumulation. ● P229F-00 - NOX Sensor Circuit Range/Performance - Bank 1. ● P2281-00 - Air Leak Between MAF And Throttle Body. ● P0087-00 - Fuel Rail Pressure Too Low. ● P2540-00 - Low Pressure Fuel System Sensor Circuit Range/Performance. ● P2543-00 - Low Pressure Fuel System Sensor Circuit Intermittent. ● P214D-00 - SCR NOx Catalyst Outlet Temperature Too High During Particulate Filter Regeneration. ● P242B-00 - Exhaust Gas Temperature Sensor Circuit Performance - Bank 1 Sensor 3. ● P24DA - Particulate Matter Sensor Exhaust Sample Error Bank 1. ● P20EE-00 - SCR NOx Catalyst Efficiency Below Threshold - Bank 1 Catalyst 1. ● P226C-00 - Turbocharger Boost Control "A" Slow Response. ● P2281-00 - Air Leak Between Maf And Throttle Body. ● P229F-00 - Nox Sensor Circuit Range/performance - Bank 1. ● P0100-00 - Mass Or Volume Air Flow Sensor "A" Circuit. ● P203F-00 - Reductant Level Too Low. ● P0423-00 - Heated Catalyst Efficiency Below Threshold Bank 1. ● P06B9-00 - Cylinder 1 Glow Plug Circuit Performance. This bulletin involves inspecting and possibly reprogramming the PCM with the latest available software.
18-025-26 REV. B	2026-07-18. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0088-00 - Fuel Rail Pressure Too High - Bank 1. ● P208B-00 - Reductant Pump 1 Control Performance. ● P2540-00 - Low Pressure Fuel System Sensor Circuit Range/Performance. ● P0506-00 - Idle Control System RPM - Lower Than Expected. ● P20CF-00 - Exhaust Aftertreatment Fuel Injector "A" Stuck Open. ● P20DB-00 - Exhaust Aftertreatment Fuel Supply Control Stuck Open. ● P040B-00 - EGR Temperature Sensor 1 Circuit Performance. ● U0109-00 - Lost Communication With Fuel Pump Control Module. ● P1451-00 - Diesel Particulate Filter System Performance. ● P2463-00 - Diesel Particulate Filter Restriction - Soot Accumulation Bank 1. ● P1191-00 - Inlet Air Temperature Sensor Rational/Performance. ● P242F-00 - Diesel Particulate Filter Restriction - Ash Accumulation. ● P229F-00 - NOX Sensor Circuit Range/Performance - Bank 1. ● P2281-00 - Air Leak Between MAF And Throttle Body. ● P0087-00 - Fuel Rail Pressure Too Low. ● P2540-00 - Low Pressure Fuel System Sensor Circuit Range/Performance. ● P2543-00 - Low Pressure Fuel System Sensor Circuit Intermittent. ● P214D-00 - SCR NOx Catalyst Outlet Temperature Too High During Particulate Filter Regeneration. ● P242B-00 - Exhaust Gas Temperature Sensor Circuit Performance - Bank 1 Sensor 3. ● P24DA - Particulate Matter Sensor Exhaust Sample Error Bank 1. ● P20EE-00 - SCR NOx Catalyst Efficiency Below Threshold - Bank 1 Catalyst 1. ● P226C-00 - Turbocharger Boost Control "A" Slow Response. ● P2281-00 - Air Leak Between Maf And Throttle Body. ● P229F-00 - Nox Sensor Circuit Range/performance - Bank 1. ● P0100-00 - Mass Or Volume Air Flow Sensor "A" Circuit. ● P203F-00 - Reductant Level Too Low. ● P0423-00 - Heated Catalyst Efficiency Below Threshold Bank 1. ● P06B9-00 - Cylinder 1 Glow Plug Circuit Performance. This bulletin involves inspecting and possibly reprogramming the PCM with the latest available software.
18-061-26 REV. A	2026-07-08. Service bulletin. SA Market Only - Flash: Powertrain Control Module (PCM) Updates Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must SYMPTOM: exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P0088-00 - Fuel Rail Pressure Too High - Bank 1. ● P0263-00 - Cylinder 1 Contribution/Balance. ● P0266-00 - Cylinder 2 Contribution/Balance. ● P0269-00 - Cylinder 3 Contribution/Balance. ● P0272-00 - Cylinder 4 Contribution/Balance. ● P0275-00 - Cylinder 5 Contribution/Balance. ● P0278-00 - Cylinder 6 Contribution/Balance. Customers may also comment one or more of the following: ● The engine runs rough and exhibits stumbling and shaking. ● Loss of power. NOTE: The perceived loss of power is due to an insufficient injector/torque response. This bulletin involves inspecting and possibly reprogramming the PCM with the latest available software.
9100841 Rev 1	2026-07-02. Service bulletin. If customer concern diagnosis leads to suspect u-joint issue with the prop shaft, u-joint service kit should be utilized to fix concern. Prop shaft replacement would not be required.
18-002-26 REV. B	2026-07-02. Service bulletin. Flash: Powertrain Control Module (PCM) Updates Customers may experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle may exhibit/set one or more of the following Diagnostic Trouble Codes (DTCs): ● P219A - Bank 1 Air-Fuel Ratio Imbalance Bank 1. ● P219B - Bank 2 Air-fuel Ratio Imbalance. NOTE: This revision has an updated and more effective fix for DTC P219B than the prior version. Customers may also comment on one or more of the following: ● Power Take-Off (PTO) may cancel during engagement with high PTO loads. ● PTO not auto-resuming after hard-wired remote start (DD/DP Only). ● Engine speed surging, unstable, or oscillating while coasting at low vehicle speeds. ● Stationary Idle PTO feature is not activating when the user configuration is selected to require parking brake be set (DD/DP Only). In addition, the following software enhancement(s) is available: ● Increase the duration that Power Takeoff related messages are displayed on the Instrument Panel Cluster (IPC) (DD/DP Only) This bulletin involves inspecting and possibly reprogramming the PCM with the latest available software.
9100841	2026-07-02. Service bulletin. HD Front and Rear Prop Shafts Increase U-Joint Usage If customer concern diagnosis leads to suspect u-joint issue or failure with the prop shaft, u-joint service kit should be utilized to fix concern. Prop shaft replacement would not be required.