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Service bulletins for the 2021 Ram 4500

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.

445 on file from NHTSA, as of 2026-10-19.

By type

By component

By trouble code

Bulletins, newest first
1036212025-03-04. Service bulletin. SERVICE BRAKES. MODULE - ANTI-LOCK BRAKE SYSTEM
1032892025-03-04. Service bulletin. BACK OVER PREVENTION: WARNINGS; LANE DEPARTURE: BLIND SPOT DETECTION. CAMERA - REAR VIEW
1032882025-03-04. Service bulletin. LANE DEPARTURE: BLIND SPOT DETECTION. CAMERA - REAR VIEW
03-001-25 REV. B2025-03-04. Service bulletin. UNKNOWN OR OTHER. "Clicking Noise While In 4WD Customers may experience the following: ● Ratcheting, click, or clicking noise in 4WD while turning. This bulletin involves replacing the front driveshaft."
91005002025-02-26. Service bulletin. ELECTRICAL SYSTEM. Touchscreen For all infotainment system repairs (touchscreens, radios, etc.), refurbished parts may be available. Follow the Infotainment Ordering guide available under the "Parts" section of Dealer Connect: DealerCONNECT> Parts> News& Information> Audio & Electronic Products Exchange Process
03-001-25 REV. A2025-02-19. Service bulletin. POWER TRAIN; UNKNOWN OR OTHER. "Clicking Noise While In 4WD Customers may experience the following: ● Ratcheting, click, or clicking noise in 4WD while turning. This bulletin involves replacing the front driveshaft."
03-001-252025-02-11. Service bulletin. POWER TRAIN. "Clicking Noise While In 4WD ustomers may experience the following: ● Ratcheting, click, or clicking noise in 4WD while turning. his bulletin involves replacing the front driveshaft"
90039802025-01-29. Service bulletin. ELECTRICAL SYSTEM. SWITCH Headlamp Before replacing the Headlamp Switch for faulty dimmer operation. Please follow the next steps to corroborate if the Headlamp Switch is malfunctioning: 1.- Please disconnect and reconnect the headlamp Switch. And verify if the issue is corrected. 2.- Review the internal resistance of the switch: a.- For the Right Dimmer (IP) between Pins 6 & 3. The value should be around 5.74 KOhms, when in the lowest position to 311 ohms in the top position (Parade Detent). b.- For the left Dimmer (Ambient Light) between pins 8 & 3. The value should be around 14.52 KOhms, when in the lowest position to 182 ohms in the top position. If a problem is found in the resistor values. Please replace the Switch.
S1408000384 REV.H2025-01-28. Service bulletin. ELECTRICAL SYSTEM. Start Stop Charging Warning Lamp Illuminated On, Intelligent Battery Sensor (IBS) State of Charge (SOC) Inaccurate, Battery Charging Message, Presence of IBS Related Diagnostic Trouble Codes (DTCs), or Battery Warning Lamp On
S1425000019 REV.A2025-01-23. Service bulletin. UNKNOWN OR OTHER. Malfunction Indicator Lamp (MIL) Illuminated. Diesel Exhaust Fluid (DEF) System Diagnostic Trouble Codes (DTCs) due to Hydrocarbon Contamination.
S1408000384 REV.G2025-01-09. Service bulletin. ELECTRICAL SYSTEM. Start Stop Charging Warning Lamp Illuminated On, Intelligent Battery Sensor (IBS) State of Charge (SOC) Inaccurate, Battery Charging Message, Presence of IBS related Diagnostic Trouble Codes (DTCs), or Battery Warning Lamp On
1023872025-01-04. Service bulletin. POWER TRAIN. SEAL - OUTPUT SHAFT
1023892025-01-04. Service bulletin. POWER TRAIN. SEAL - OUTPUT SHAFT
S2008000186 REV.B2024-12-21. Service bulletin. ENGINE. Engine Control Module (ECM) Flash Failure, Diagnostic Trouble Code (DTC) U1601 – ECU Application Software Code 1 Missing Or Corrupted
S2208000045 REV.B2024-12-11. Service bulletin. BACK OVER PREVENTION: REARVIEW SYSTEM BRAKING. Backup Camera Poor Image Quality Inspection
25-008-242024-11-18. Service bulletin. UNKNOWN OR OTHER. "Flash: Diesel Exhaust Fluid (DEF) Dosing Control Unit (DCU) Update Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set the following Diagnostic Trouble Code (DTC): ● P21C4-00 - Reductant Line Heater Relay Control Circuit High. ● U11C1-00 - Reductant Control Module Received Implausible Data From ECM/PCM. These DTCs will occur after installation of service DCU 68458603AB. This bulletin involves reprogramming the DCU with the latest available software."
S2422000001 REV.C2024-11-13. Service bulletin. WHEELS; ELECTRICAL SYSTEM. Tire Pressure Monitor (TPM) Service Information. TPM Lamp On.
1004982024-11-01. Service bulletin. ENGINE. MODULE - ENGINE CONTROLLER
1007742024-11-01. Service bulletin. ELECTRICAL SYSTEM. SWITCH - HEADLAMP
08-222-242024-10-14. Service bulletin. SERVICE BRAKES. "Flash: Anti-Lock Brake System (ABS) Module 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):** ● **C2200-47 - Anti-Lock Brake Module Internal - Watchdog / Safety Auc Failure.** ● C006A-49 - Multi-Axis Acceleration Sensor - Internal Electronic Failure. Customers may also comment on one or more of the following: ● **Anti-lock Brake System (ABS) indicator light illuminated in the Instrument Panel Cluster (IPC). ● Electronic Stability Control (ESC) indicator light illuminated in the IPC. ● The Red Brake Warning indicator light illuminated in the IPC.** This bulletin involves reprogramming the ABS with the latest software available."
S24220000032024-10-10. Service bulletin. WHEELS. Trailer Tire Pressure Monitor (TTPM) Programming Tips And Operation Information.
25-006-242024-10-08. Service bulletin. UNKNOWN OR OTHER; ENGINE. "Diesel Exhaust Fluid (DEF) Fluid Freezing Warranty Extension XR1 Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set the following Diagnostic Trouble Code (DTC): ● P203E-00 - Reductant Level Sensor 1 Circuit Intermittent-Erratic. Customers may also experience one or more of the following: ● Repeated freeze/thaw cycles of the urea tank to cause solid DEF crystals to form and settle on the focus tube, blocking the level sensor signal. ● Rapid temperature swings from below freezing to above freezing causing an incomplete thaw of the DEF tank. When the vehicle is powered on, the diagnostic is enabled due to thawed DEF at the tank bottom surface, but the fluid in the center is still partially frozen. ● Not following the proper DEF fill procedure and overfilling the tank. This bulletin involves replacing the urea delivery module and possibly updating the Dosing Control Unit (DCU) software"
25-007-242024-10-08. Service bulletin. UNKNOWN OR OTHER; ENGINE. "Diesel Exhaust Fluid (DEF) Fluid Freezing Customers must experience a Malfunction Indicator Lamp (MIL) illumination and the vehicle must exhibit/set the following Diagnostic Trouble Code (DTC): ● P203E-00 - Reductant Level Sensor 1 Circuit Intermittent-Erratic. Customers may also experience one or more of the following: ● Repeated freeze/thaw cycles of the urea tank to cause solid DEF crystals to form and settle on the focus tube, blocking the level sensor signal. ● Rapid temperature swings from below freezing to above freezing causing an incomplete thaw of the DEF tank. When the vehicle is powered on, the diagnostic is enabled due to thawed DEF at the tank bottom surface, but the fluid in the center is still partially frozen. ● Not following the proper DEF fill procedure and overfilling the tank This bulletin involves replacing the urea delivery module and grade vent valve and updating the Dosing Control Unit (DCU) software This bulletin involves replacing the urea delivery module and possibly updating the Dosing Control Unit (DCU) software"
978022024-10-08. Service bulletin. ELECTRICAL SYSTEM. SWITCH - HEADLAMP
S24230000432024-10-04. Service bulletin. ELECTRICAL SYSTEM. Dome Lamp LED And Incandescent Bulb Servicing.

The summaries are NHTSA's. Each bulletin's page links NHTSA's copy of the manufacturer's document.