P0841 on 2024 Ram 2500: Transmission Pressure Sensor Circuit Causes & Fixes

What's Unique About the 2024-2024 Ram 2500

For the 2024 Ram 2500, the diagnosis depends heavily on the transmission. Models with the 6.7L Cummins diesel are often equipped with the 6-speed 68RFE, while some gas engine models may use a ZF 8-speed automatic. A critical Technical Service Bulletin (TSB #21-012-25 REV. E) for the 68RFE-equipped trucks built between June and September 2024 indicates a known issue where P0841 (among other codes) may require a complete transmission replacement. For trucks outside this build window or with the ZF transmission, the cause is more likely a software glitch, a faulty sensor, or a wiring problem.

Diagnostic Flowchart

Tap your situation to follow the diagnostic path that matches what you're seeing on this vehicle.

Symptoms You May Notice

• Check Engine Light or Transmission Warning Light is on
• Harsh, erratic, or delayed shifting
• Transmission slipping between gears
• Vehicle may enter "limp mode" (stuck in one gear)
• Reduced fuel economy
• Difficulty accelerating or vehicle stalls when put in gear
• Inability to shift into higher gears, such as 5th or 6th
🎬 Watch: A quick breakdown of P0841 causes and common fixes.

Most Likely Causes

1. Low or Dirty Transmission Fluid 🔴 High Probability Improper fluid level or contaminated fluid is a leading cause of incorrect pressure readings across all automatic transmissions. A clogged filter or improperly seated spin-on filter seal can also cause a loss of prime and trigger this code.
   How to confirm: Check the transmission fluid level and condition. Note that modern Ram trucks do not have a traditional dipstick, requiring a specific procedure to check the fluid at the fill plug at a specific temperature. 🎬 See this guide on checking fluid levels without a dipstick. The fluid should be at the correct level and not appear dark, burnt, or contain debris.
   Typical fix: Perform a transmission fluid and filter change. Ensure the correct OEM-specified fluid (e.g., Mopar ZF 8&9 Speed ATF for the ZF, Mopar ATF+4 for the 68RFE) is used.
   Est. part cost: $100-$250
2. Faulty Transmission Fluid Pressure Sensor/Switch 🔴 High Probability On the 68RFE transmission, the pressure sensor (transducer) is a known failure item. It is part of the larger solenoid/TRS assembly on the valve body. On ZF 8-speed transmissions, the sensors are integrated into the expensive mechatronics unit, making replacement more complex.
   How to confirm: Using a diagnostic scan tool with live data capability (like AlfaOBD), monitor the pressure reading from the sensor. The sensor and its circuit can also be tested with a multimeter for proper voltage and resistance according to the service manual.
   Typical fix: For the 68RFE, replace the faulty transmission pressure transducer, which is often done by replacing the entire solenoid pack assembly inside the transmission oil pan. 🎬 Watch: The right way to replace a 68RFE solenoid pack. For the ZF 8-speed, this may require replacement of the entire mechatronics (valve body) unit.
   Est. part cost: $50-$400
3. Wiring or Connector Issue 🟡 Medium Probability
   How to confirm: Visually inspect the wiring harness and connector going to the transmission for any signs of damage, corrosion, or loose connections. A user on a Cummins forum noted that wiring issues along the frame rail and near the driver's side mudflap are common points of failure. A "wiggle test" on the harness while monitoring live sensor data can help identify intermittent connection problems.
   Typical fix: Repair or replace the damaged section of the wiring harness or clean/replace the connector.
   Est. part cost: $10-$150
4. Software Glitch / Outdated Control Module Software 🟡 Medium Probability The existence of TSB #21-012-25 REV. E for the 2024 model year specifically points to software as a potential cause that the manufacturer has identified. Other TSBs for similar platforms also call for PCM reprogramming to fix shifting anomalies.
   How to confirm: A Ram dealership or a qualified shop with access to OEM software (wiTECH) can check if the vehicle's PCM/TCM software is up-to-date and if any updates related to the TSB are available.
   Typical fix: Reprogram the Powertrain Control Module (PCM) or Transmission Control Module (TCM) with the latest manufacturer software. In the case of TSB 21-012-25 REV. E for certain 2024 models, the fix is a full transmission replacement.
   Est. part cost: $0-$200 (for software update)

Rare But Worth Checking

• Internal Transmission Mechanical Failure: While less common, issues like a failing internal clutch pack, a sticking valve in the valve body, a cut No. 1 check ball, or a dislodged reverse carrier snap ring can cause the pressure irregularities that trigger P0841. This is usually suspected after fluid, sensor, and wiring issues have been ruled out. A Reddit user with a similar issue on a 68RFE ultimately needed a valve body replacement.
• Faulty Powertrain/Transmission Control Module (PCM/TCM): This is a rare cause. The control module itself can fail, but it should only be considered for replacement after all other possible causes have been exhaustively diagnosed and eliminated. One owner on a forum traced their P0841 issue to a faulty PCM after replacing the sensor and checking wiring.

Diagnosis Steps

1. Check and record any and all stored DTCs with an OBD-II scanner.
2. Inspect the transmission fluid level and condition. Ensure it is clean, full, and of the correct type.
3. Visually inspect the transmission's main electrical connector and wiring harness for any signs of corrosion, damage, or loose connections, paying attention to the harness routing along the frame.
4. Use a scan tool to monitor live data from the Transmission Fluid Pressure Sensor 'A'. Compare the readings to manufacturer specifications at idle and in different gears.
5. Check for any available Technical Service Bulletins (TSBs), especially TSB 21-012-25 REV. E, which applies to specific 2024 Ram 2500s with the 68RFE transmission and may direct a transmission replacement.
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.
7. If the sensor and wiring test good, the issue may be a faulty sensor/solenoid assembly. For the 68RFE, this requires removing the transmission pan for replacement.
8. If a new sensor does not resolve the issue, further diagnosis of the valve body (checking for sticking valves or cut check balls) or internal transmission components by a professional may be necessary.

Parts You'll Likely Need

• Transmission Fluid Pressure Sensor/Transducer (OEM #4799758AF (For 68RFE Transmissions)) — This is the most common hardware failure that directly causes the P0841 code when fluid and wiring are confirmed to be good. Note: This part is often part of the larger solenoid block.
  Trusted brands: Mopar, Dorman (601-215), Standard Motor Products (SMP)
  OEM price range: $75-$110
  Aftermarket price range: $40-$90
• Transmission Fluid and Filter Kit — Low or contaminated fluid is a primary cause of pressure-related codes. A service is a fundamental first step.

Related Codes That Often Appear With This One

• P0868 — P0868 indicates 'Transmission Fluid Pressure Low', which is a direct mechanical cause for the performance code P0841. They often appear together when the fluid is low or there's a pump/leak issue.
• P0871 — This code relates to 'Transmission Fluid Pressure Sensor/Switch 'C' Circuit'. Seeing it with P0841 ('A' circuit) could indicate a widespread electrical or hydraulic problem affecting multiple sensors or a failing solenoid block.
• P0731, P0732, P0733, P0734, P0735, P0736 — These codes indicate 'Incorrect Gear Ratio' for various gears. Incorrect fluid pressure can prevent clutches from engaging properly, leading to gear slip and these ratio codes, as noted in TSB 21-012-25 REV. E.
• P0944 — This code for 'Loss of Hydraulic Pump Prime' is often a precursor to pressure rationality codes like P0841. Service manuals advise diagnosing P0944 first, as it points to a fundamental fluid supply issue like a bad filter seal or low fluid level.

Technical Service Bulletins (TSBs) & Recalls

• 21-012-25 REV. E: Addresses P0841 along with other transmission codes like P0733, P0734, P0868 for 2024 Ram 2500/3500 trucks with the 68RFE. For vehicles within a specific build date range, the prescribed repair is transmission replacement.

Platform-Specific Known Issues

• NHTSA TSB 21-012-25 REV. E specifically lists P0841 for 2024 Ram 2500 trucks with the 6.7L Cummins and 68RFE transmission, built between June and September 2024. The bulletin's repair procedure is to replace the entire transmission, indicating a potentially serious manufacturing defect in this batch.
• On Reddit, an owner of a 68RFE-equipped truck with P0841 replaced the sensor and valve body without success, leading to suspicion of a wiring or PCM issue, which are known secondary causes.
• Forums for older Ram models with similar transmissions show a history of this code being caused by loose valve body bolts or improperly installed spin-on filters, which are worth checking during a fluid service.

Mechanic-Grade Diagnostic Values

• Resistance of (T50) L/R Pressure Switch Sense Circuit — expected: Less than 5.0 ohms between the solenoid connector and the PCM connector.. Failure: Resistance above 5.0 ohms indicates an open in the circuit.
• Resistance to Ground of (T50) L/R Pressure Switch Sense Circuit — expected: Above 5.0 ohms.. Failure: Resistance below 5.0 ohms indicates a short to ground.
• Scan Tool 'Desired Line Pressure' vs. 'Actual Line Pressure' — expected: Actual pressure should closely track desired pressure during operation.. Failure: A significant and consistent difference between the two values points to a hydraulic or sensor issue.
• Input/Output Speed Sensor Resistance — expected: Approximately 535 ohms at room temperature.. Failure: A reading significantly different from 535 ohms may indicate a faulty speed sensor, which can affect pressure calculations.

Scan Tool Commands That Help

• wiTECH, AlfaOBD, or equivalent: Monitor Pressure Switch State (Open/Closed) — Used during diagnosis to see if the PCM is receiving the correct electrical state from the pressure switch for the current gear. This helps differentiate a hydraulic fault from an electrical one.
• wiTECH, AlfaOBD, or equivalent: Quick Learn Procedure — This must be performed after replacing the valve body, solenoid pack, or the entire transmission. It resets and relearns the clutch volume indexes (CVIs) and shift adapts. Failure to do this will result in poor shifting and may set new codes.
• wiTECH or equivalent dealer tool: TCM/PCM Reset — Can be used after a repair to clear adaptive memory. It is also a step in the diagnostic process if a software glitch is suspected.
• Miller Tool #8333 Transmission Simulator: Pressure Switch Test — This specialized tool connects in place of the transmission and allows a technician to manually open and close the pressure switch circuits. While watching the scan tool, the tech can confirm the integrity of the wiring harness and PCM, completely isolating them from the transmission internals.

Wiring & Ground Locations

• (T50) L/R Pressure Switch Sense circuit — This wire runs from the main transmission harness connector to the Powertrain Control Module (PCM).. This is the specific signal wire for the sensor in question. Service manuals direct technicians to test this wire for opens or shorts between the transmission and PCM connectors.
• Main Transmission Harness Connector — On the left side of the 68RFE transmission case.. This is the primary connection point for all transmission electronics. It is susceptible to corrosion, debris, and damage, which can cause P0841 and other codes.
• Frame Rail Harness Chafe Point — Along the frame rail, particularly near the driver's side mudflap area.. Forum users report this as a common, but often overlooked, location for the transmission wiring harness to rub through and short out, causing intermittent pressure sensor codes.
• G106 — Typically located on the left rear of the engine compartment.. This is a major engine and control module ground point. A poor connection here can cause erratic behavior and false codes from various sensors, including those in the transmission.

Real Owner Repair Stories

• Reddit user on r/Cummins (Ram truck with 68RFE, 112k miles) — P0841 code, hard/late shifting, no overdrive. Clearing the code made it shift normally for 10-15 miles before the code returned.
  ❌ Tried (didn't work) Replaced the pressure sensor, Replaced the valve body, Performed a transmission fluid and filter change
  ✅ What actually fixed it The final fix was not posted by the owner, but a master tech commented that after trying those parts, the cause is almost always a wiring issue along the frame rail or a faulty PCM. The intermittent nature strongly pointed to an electrical fault, not a mechanical one.
• RamForum.com user (2016 Ram 2500 5.7L) — P0868 (Transmission Fluid Pressure Low) code appeared immediately after purchase. Fluid on dipstick was bubbly.
  ❌ Tried (didn't work) Initially suspected internal transmission parts failure.
  ✅ What actually fixed it The owner checked the fluid level correctly (at temp, in neutral) and found it was overfilled by 3.25 quarts. After removing the excess fluid, the shifting improved and the code went away on its own. This highlights how critical the basic fluid check is before replacing parts.

"I Checked Everything" — The Actual Cause

• In the context of P0841, the equivalent of a 'smoke test clean' scenario is when the fluid level is correct, the filters are new, and a new pressure sensor/solenoid pack does not fix the problem. In these cases, the root cause is almost always either a hard-to-find wiring issue (intermittent short/open) or a deeper mechanical problem in the valve body. Technicians report that a flexing solenoid pack circuit board can also cause false codes that a simple sensor swap won't fix.

OEM Part Supersession History

• Varies (e.g., 52119435AF) → Varies (e.g., 68376695AA) — Internal design updates and improvements by Mopar.
  Heads up: Crucially, 68RFE solenoid packs are NOT universally compatible. Gen 1 (2007.5-2010) used a white connector. Gen 2 (2011-2018) used a grey connector. Gen 3 (2019+) uses a blue connector. You must use the correct color connector for your model year range.
• 4799758AD → 4799758AF — Part revision for the individual line pressure sensor/transducer.
  Heads up: While this sensor can be bought individually, it is part of the solenoid pack assembly. Most shops replace the entire solenoid pack to prevent comebacks, as other sensors or solenoids in the pack may be near failure.

Model Year Variations Within This Range

• 2019-Present (Gen 3 68RFE): These transmissions use a solenoid pack with a blue electrical connector. It is not interchangeable with the earlier white (Gen 1) or grey (Gen 2) connector packs.
• 2011-2018 (Gen 2 68RFE): These transmissions use a solenoid pack with a grey electrical connector and have a 5-check-ball valve body design.
• 2007.5-2010 (Gen 1 68RFE): Considered the most problematic generation, these use a solenoid pack with a white electrical connector and a 7-check-ball valve body. The valve body and pump are made of a softer metal prone to faster wear.