WenmarOpen by Wenmar Pro

P242B on the 2026 Ram 2500

The bulletins listed name this code in NHTSA's summary, or are about the same components. A bulletin or a recall listed here may apply to the model year. None of it is a diagnosis.

Nobody has written a description of this code yet.

Bulletins for this model year that name P242B
18-067-262026-07-18. 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. B2026-07-18. 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. A2026-05-28. Service bulletin. Flash: Powertrain Control Module (PCM) 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): ● **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. ● P06BA-00 - Cylinder 2 Glow Plug Circuit Performance. ● P06BB-00 - Cylinder 3 Glow Plug Circuit Performance. ● P06BC-00 - Cylinder 4 Glow Plug Circuit Performance. ● P06BD-00 - Cylinder 5 Glow Plug Circuit Performance. ● P06BE-00 - Cylinder 6 Glow Plug Circuit Performance. ● P020A-00 - Cylinder 1 Injection Timing. ● 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. ● P026B-00 - Injection Timing Performance. Customers may experience one or more of the following: ● **An eventual 8 kph (5 mph) vehicle speed derate if the issue does not selfheal.** ● Instrument Panel Cluster (IPC) related messages: ○ Desoot Required. ○ Soot Filter Nearly Full. ○ Exhaust Filter Full Power Reduced See Dealer. ● Long engine crank times, particularly after fuel filter change. ● Inverter drops out when shifting from park to drive. ● Diesel Exhaust Fluid level gauge inaccuracy. ● Poor cold start performance. This bulletin involves inspecting and possibly reprogramming the PCM with the latest available software.
S26250000032026-04-10. Service bulletin. Active/Pending Diagnostic Trouble Code (DTC) P24A0, P2482, P2481, P0420, P2470, P2471, P2472, P242D, P242B, P244D, P1484, P106D, P1060 And/or P354B Setting In The Powertrain Control Module (PCM)
18-025-262026-03-05. 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): ● **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. ● P06BA-00 - Cylinder 2 Glow Plug Circuit Performance. ● P06BB-00 - Cylinder 3 Glow Plug Circuit Performance. ●
18-101-252025-11-26. Service bulletin. Flash: Powertrain Control Module (PCM) 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): ● 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. ● P06BA-00 - Cylinder 2 Glow Plug Circuit Performance. ● P06BB-00 - Cylinder 3 Glow Plug Circuit Performance. ● P06BC-00 - Cylinder 4 Glow Plug Circuit Performance. ● P06BD-00 - Cylinder 5 Glow Plug Circuit Performance. ● P06BE-00 - Cylinder 6 Glow Plug Circuit Performance. ● P020A-00 - Cylinder 1 Injection Timing. ● 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. ● P026B-00 - Injection Timing Performance. Customers may experience one or more of the following: ● Inverter drops out when shifting from park to drive. ● Diesel Exhaust Fluid level gauge inaccuracy This bulletin involves reprogramming the PCM with the latest available software.
OTHERDOC_1472025-09-10. Over-the-air update. Powertrain Contol Module Over The Air Update to V2B (Diesel Only) Software Version (FOTA) 2025 - 2026 (DJ) RAM 2500 Pickup 2025 - 2026 (D2) RAM 3500 Pickup 2025 - 2026 (DD) RAM 3500 Cab Chassis 2025 - 2026 (DF) RAM 3500 10K Lb. Cab Chassis2025 - 2026 (DP) RAM 4500/5500 Cab Chassis Customers may experience one or more of the following: - Power Inverter (110V connection) drops out when shifting from P to D - DEF (Diesel Exhaust Fluid) level gauge inaccuracy - Poor cold start performance - Instrument Panel Cluste MIL (Malfunction Indicator Light) ON; Possible P-codes: P0087/P2540/P2543 Fuel Pressure P214D/P242B SCR Temperature P24DA PM Sensor P20EE SCR Efficiency P226C/P2281 Mass Charge Flow P229F System Outlet NOx Sensor P0100 MAF Sensor P203F DEF Level P0423 DOC Efficiency

7 on file from NHTSA, as of 2026-10-19. See them in the bulletin list. A bulletin lists model years: read the document for which vehicles it concerns.