P0841 on 2024 Ram 2500 6.7L Cummins: Transmission Pressure Sensor Causes and Fixes

What's Unique About the 2024-2024 Ram 2500

For the 2024 Ram 2500 with the 6.7L Cummins and 68RFE transmission, this code has a very specific and serious meaning for a subset of vehicles. TSB #21-012-25 REV. E applies to trucks built between June 14, 2024, and September 04, 2024. For this specific group, P0841, often with other codes like P0868 (low pressure) and multiple gear ratio errors, points to a cracking rear selective thrust bearing, and the only authorized repair is a complete transmission replacement. For trucks outside this build window, the cause is more likely a traditional sensor, fluid, or wiring issue.

Symptoms You May Notice

• Check Engine Light (Malfunction Indicator Lamp) is on
• Transmission may be stuck in one gear ('limp mode')
• Harsh, erratic, or delayed shifting
• Loss of overdrive gear
• Transmission slipping
• Vehicle may stall when put into gear
• Clearing the code may temporarily restore normal shifting for a short period before the code returns

Most Likely Causes

1. Low or Dirty Transmission Fluid 🟡 Medium Probability These trucks work hard, and fluid can break down or be consumed by small leaks. The 68RFE is also sensitive to fluid level and condition; an incorrect level or clogged filters can directly cause pressure rationality codes. A recall (ZA3 / 22V-835) was issued for 2020-2023 models for fluid being expelled from the dipstick tube, highlighting the system's sensitivity to pressure and heat.
   How to confirm: Check the transmission fluid level and condition using the dipstick. The fluid must be checked when hot, with the engine running, and the transmission in neutral. The fluid should be at the correct level, red in color (Mopar ATF+4), and not smell burnt.
   Typical fix: Top off with the correct fluid (MOPAR ATF+4 for the 68RFE) or perform a fluid and filter change. 🎬 Watch a full 68RFE transmission fluid and filter service walkthrough It is critical to ensure the sump filter O-ring is seated correctly, as a cracked or improperly installed seal is a very common cause of pressure issues after a service.
   Est. part cost: $50-$200
2. Faulty Transmission Fluid Pressure Sensor/Switch 🔴 High Probability The sensor is part of the solenoid/TRS assembly (solenoid pack) on the valve body, which is a widely-documented common failure point on the 68RFE transmission. It lives in a harsh environment of heat and pressure and can fail electrically or become clogged with debris.
   How to confirm: A professional scan tool can monitor live data from the L/R pressure switch to see if its state ('open' or 'closed') is illogical for the commanded gear. The sensor's circuit can also be tested with a multimeter for opens or shorts. A Reddit user with a 68RFE reported replacing the sensor and even the valve body did not fix their P0841, pointing toward a more elusive wiring or PCM issue in their case.
   Typical fix: Replace the transmission solenoid/TRS assembly, which contains the pressure switches. This requires removing the transmission pan and valve body. 🎬 Watch this step-by-step guide to replacing the 68RFE solenoid pack For 2019+ models, this is a 'blue connector' style solenoid pack.
   Est. part cost: $250-$450
3. Wiring or Connector Issues 🟡 Medium Probability The wiring harness to the transmission is exposed to road debris, heat, and vibration. Forum users report a common chafe point for the transmission harness is along the frame rail, especially near the driver's side mudflap area, which can cause intermittent shorts and trigger this code.
   How to confirm: Visually inspect the wiring harness leading to the transmission for any damage, particularly along the frame. Check the main connector for corrosion or pushed-out pins. A multimeter can be used to check for opens or shorts in the (T50) L/R Pressure Switch Sense circuit.
   Typical fix: Repair the damaged section of wiring or clean/replace the affected connector.
   Est. part cost: $10-$100

Rare But Worth Checking

• Cracked Rear Selective Thrust Bearing (Specific 2024 Models): This is the primary cause for trucks built between June 14 and September 4, 2024, per TSB 21-012-25 REV. E. If your truck falls in this build range and has P0841 along with codes like P0868 or gear ratio errors, this is the most likely cause, and it requires a full transmission replacement.
• Faulty Valve Body: A sticking solenoid switch valve (SSV) or internal leak within the valve body can cause pressure irregularities that trigger this code. This is usually suspected after the sensor and wiring have been ruled out. Vacuum testing the valve body can confirm this diagnosis.
• Faulty Powertrain Control Module (PCM) or Transmission Control Module (TCM): This is a very rare cause. The PCM/TCM should only be considered after all other possibilities, including wiring, sensors, and internal mechanical issues, have been thoroughly exhausted. A technician in a forum noted that when sensor and valve body replacement fails, the cause is often a wiring issue or a faulty PCM.

Diagnosis Steps

1. Check for and document any other stored DTCs, paying close attention to P0868 or gear ratio codes.
2. Using a scan tool, check for any applicable Technical Service Bulletins (TSBs), especially TSB 21-012-25 REV. E, to see if the vehicle's VIN falls within the specified build dates (June 14, 2024 - Sept 04, 2024) for transmission replacement.
3. Check the transmission fluid level and condition. The engine must be running, the transmission hot, and in neutral. Ensure it is full and not burnt or contaminated.
4. Inspect the transmission wiring harness and connectors for any visible damage, corrosion, or loose pins, especially along the frame rail.
5. Use a professional scan tool to monitor the L/R Pressure Switch state in real-time. Observe if the sensor's state ('Open'/'Closed') changes correctly when shifting gears and matches the expected state for the current gear.
6. If the sensor readings are erratic or incorrect and the wiring is intact, test the sensor's circuit for proper voltage, ground, and signal integrity using a multimeter and wiring diagrams. Check the (T50) L/R Pressure Switch Sense circuit for opens or shorts to ground.
7. If the circuit tests good, the likely culprit is the sensor/solenoid assembly itself. This requires removing the transmission pan for replacement.
8. If all electrical components and fluid are good, the issue may be an internal mechanical problem with the valve body (e.g., cut No. 1 check ball, sticking valve) or other components, requiring more advanced transmission diagnostics.

Parts You'll Likely Need

• Transmission Solenoid / Pressure Switch Assembly (OEM #68456067AA (for 2019+ 'Blue Connector' style)) — This assembly contains the pressure switches that commonly fail. For the 68RFE, these switches are integral to the solenoid block, which is the most common part replaced to fix this code when fluid and wiring are okay.
  Trusted brands: Mopar, Rostra, Revmax
  OEM price range: $350-$640
  Aftermarket price range: $150-$400

Related Codes That Often Appear With This One

• P0868 — Indicates 'Transmission Fluid Pressure Low'. This code is often seen with P0841 because low overall pressure can cause the sensor's readings to be out of the expected range. Both are listed together in TSB 21-012-25 REV. E.
• P0871 — Relates to the 'Transmission Fluid Pressure Sensor/Switch 'C' Circuit'. Seeing multiple pressure sensor codes together can point to a widespread electrical issue, a failing solenoid block, or a significant hydraulic problem.
• P0731-P0735 — These are 'Incorrect Gear Ratio' codes. They can be triggered when the TCM detects a mismatch between engine speed and output speed, which can happen if a clutch pack isn't engaging correctly due to the pressure issue indicated by P0841.
• P0944 — Indicates 'Loss of Hydraulic Pump Prime'. This is a serious code that points to a fundamental lack of pressure in the system, which would naturally cause pressure sensor rationality codes like P0841.

Technical Service Bulletins (TSBs) & Recalls

• 21-012-25 REV. E — Applies to 2024 Ram 2500/3500 with 6.7L Cummins and 68RFE, built between June 14, 2024, and September 04, 2024. For a list of DTCs including P0841, P0868, and multiple gear ratio errors, the bulletin mandates a complete transmission replacement due to a suspected cracking rear selective thrust bearing.

Platform-Specific Known Issues

• TSB #21-012-25 REV. E: For 2024 Ram 2500 models with the 68RFE transmission built between June 14, 2024, and September 04, 2024, this code (often with others) can indicate a cracking rear selective thrust bearing. The bulletin mandates a complete transmission replacement as the only authorized repair.
• Wiring Harness Chafe: Owners and technicians report a common issue where the transmission wiring harness rubs through against the frame, causing intermittent electrical faults that can be difficult to diagnose.

Mechanic-Grade Diagnostic Values

• (T50) L/R Pressure Switch Sense Circuit Resistance — expected: Less than 5.0 ohms. Failure: A reading above 5.0 ohms indicates an open or high resistance in the circuit between the solenoid assembly and the TCM.
• (T50) L/R Pressure Switch Sense Circuit Resistance to Ground — expected: Infinite or Over-Limit (OL). Failure: Any reading less than infinity (e.g., under 5.0 ohms) indicates a short to ground in the circuit.
• Clutch Volume Index (CVI) for Low/Reverse Clutch — expected: Typically 20-75 (Varies by wear). Failure: A CVI value of 0 or a very high number (over 100) can indicate a failed clutch pack, major leak, or sensor issue. This is an advanced metric viewed on a scan tool.
• L/R Pressure Switch State (Scan Tool) — expected: Should read 'Closed' in Park, Neutral, and Reverse. Should read 'Open' in all forward gears.. Failure: The switch state does not match the commanded gear (e.g., reads 'Closed' in Drive), indicating a hydraulic or electrical fault.

Scan Tool Commands That Help

• wiTECH (Dealer Scan Tool): Transmission 'Quicklearn' Procedure — This procedure should be performed after replacing the valve body or solenoid pack. It allows the TCM to relearn the clutch fill volumes and apply times, which is critical for proper shift quality and preventing future codes.
• wiTECH (Dealer Scan Tool): PCM Configuration Routine — This may be required after a PCM/TCM software update or replacement to ensure all vehicle options and parameters are correctly configured.
• wiTECH or high-end aftermarket (e.g., Snap-On, Autel): View Transmission Event Data — Before clearing the code, check the event data (freeze frame). This shows the exact conditions (gear, temp, speed) when the P0841 code was set, which can help pinpoint whether the fault occurs when shifting into a specific gear or under certain loads.

Wiring & Ground Locations

• (T50) L/R Pressure Switch Sense Circuit — This wire runs from the Transmission Solenoid/TRS Assembly connector on the driver's side of the transmission case to the Transmission Control Module (TCM).. This is the specific signal wire for the Low/Reverse pressure switch. An open, short to ground, or short to voltage on this wire is a direct cause of P0841.
• Transmission Solenoid / TRS Assembly Connector — A large, round connector on the driver's side of the 68RFE transmission case.. This is the main electrical connection to the solenoid pack and all internal sensors. It is a common point for corrosion, moisture intrusion, and pushed/damaged pins, which can cause P0841 and other transmission codes.
• Harness Chafe Point — Along the frame rail, particularly near the driver's side mudflap area.. The transmission wiring harness can rub against the frame in this area, eventually wearing through the insulation and causing intermittent shorts to ground, which can trigger P0841. A 'wiggle test' of the harness in this area while monitoring sensor data can help identify this issue.

Real Owner Repair Stories

• Reddit user @imoto72 on r/Cummins (Vehicle with 68RFE, 112k miles, used for towing.) — P0841 code, hard/late shifting, no overdrive. Clearing the code would restore normal shifting for 10-15 miles before the code returned.
  ❌ Tried (didn't work) Replaced the transmission fluid pressure sensor., Replaced the entire valve body., Performed a transmission fluid flush and filter change.
  ✅ What actually fixed it The user did not post a final fix, but other technicians in the thread strongly suggested the next step was to meticulously inspect the wiring harness for chafing along the frame rail or a faulty PCM, as the primary components had already been replaced without success.

When the Usual Fixes Don't Work

• In one documented case on Reddit, a vehicle owner with P0841 replaced the pressure sensor and the entire valve body, yet the problem persisted. This strongly indicates that while the sensor and solenoid pack are the most common culprits, the issue can sometimes be more elusive, residing in the wiring harness (chafing, connector corrosion) or, rarely, the control module itself. This contradicts the idea that replacing the solenoid pack is a guaranteed fix.

OEM Part Supersession History

• 68367309AA → 68456067AA — Revision and update to the part.
• 68456067AA → 68456067AB — Further revision and update to the part for newer model years.
  Heads up: Part 68456067AB is the current recommended replacement for 2019+ Ram trucks with the 68RFE. Using an older part number may not be ideal.

Model Year Variations Within This Range

• 2019+: Starting in 2019, the 68RFE switched to a 'blue connector' solenoid pack (P/N 68456067AA and newer revisions). Pre-2019 models used a 'white connector' solenoid pack. They are not interchangeable. Furthermore, on 2019+ models, the solenoid pack is electronically coded to the vehicle's ECM/TCM. Replacing it may require a 'Quicklearn' or other programming procedure with a capable scan tool for the transmission to function correctly.

Diagnostic Flowchart

Other Known Issues on This Vehicle

Issues unrelated to this code that are worth knowing about as an owner of this generation:

• Premature Lifter/Camshaft Failure 🔴 High — A growing concern on 2019+ 6.7L Cummins engines. Failure can occur with little warning and cause catastrophic engine damage. (Ref: TSB S1709000010RevB for older models describes similar issues.)
• Emissions System Problems (DPF/EGR) 🟠 Medium — Clogged Diesel Particulate Filters (DPF) and failing EGR coolers are common across all modern diesels, including the 6.7L Cummins. This can lead to reduced power and costly repairs. (Ref: TSB #0901723 (NHTSA #10243261) is a warranty extension for the PM sensor related to the DPF system on 2021-2022 models.)
• Fuel Dilution of Engine Oil 🟠 Medium — The method the 6.7L Cummins uses for DPF regeneration involves injecting extra fuel during the exhaust stroke, which can lead to fuel contaminating the engine oil over time. This can reduce lubrication and cause premature wear, especially on the turbocharger bearings.
• Uconnect Infotainment System Glitches 🟡 Low — Owners frequently report issues like blank screens, system resets, and connectivity problems with the Uconnect system. These are typically resolved via software updates. (Ref: Multiple TSBs exist for software updates, such as 08-044-23 for 2022-2023 models.)
• Heater Grid Bolt Failure 🔴 High — While reportedly rarer in newer models, there is a known failure where a bolt from the intake air heater grid can break off and fall into the engine, typically destroying the #6 cylinder.

Used vs. New Parts: Buying Guide for This Vehicle

When a used part is the smart pick: A complete, low-mileage used transmission assembly from a reputable salvage yard can be a cost-effective solution, especially if your vehicle falls under the TSB requiring a full replacement and is out of warranty. A used valve body can also be considered if it's from a low-mileage donor and has been inspected.

Donor-vehicle mileage cap: roughly under 80000 miles for the part to have meaningful remaining life.

What to inspect on the donor part:

• Check the fluid from the donor transmission. It should be red and not smell burnt.
• Ask for the VIN of the donor vehicle to verify its build date and check for TSB/recall history.
• Inspect the main electrical connector for any signs of corrosion, melting, or damage.
• If possible, get a warranty from the salvage yard.

OEM-only on this vehicle (don't cheap out):

• Transmission Solenoid / Pressure Switch Assembly: Due to the high failure rate of aftermarket units and the electronic coding on 2019+ models, using a genuine Mopar solenoid pack is strongly recommended to avoid compatibility issues and repeat failures.

Aftermarket brands forum-validated for this vehicle:

• For valve bodies: Sonnax and Revmax are well-regarded in the diesel community for their upgraded valve bodies that address common 68RFE weak points.
• For complete transmissions: SunCoast, Revmax, and Tier One are known for building robust 68RFE transmissions that are stronger than stock.

Brands owners have reported issues with on this vehicle:

• Generic, unbranded solenoid packs from online marketplaces are frequently cited as being unreliable and failing shortly after installation.

Real Owner Stories

Aggregated from forums and TSBs cited above. Mileages and costs reflect what owners reported in those sources.

Related OBD-II Codes

• P0868 — Low Transmission Fluid Pressure; often appears alongside P0841 due to fluid level issues, clogged filters, or internal mechanical failures like a cracked thrust bearing.
• P0700 — Transmission Control System Malfunction; a general code indicating the TCM has requested the MIL be illuminated due to a transmission fault like P0841.
• P0731 — Gear Ratio Error; often accompanies P0841 in 2024 models experiencing internal mechanical failure (cracked thrust bearing) as noted in TSB 21-012-25.
• P0871 — OD Pressure Switch Rationality; a similar pressure switch code common to the RFE transmission family's solenoid pack failures.

Frequently Asked Questions