P0524 on 2021 Ram 1500: Engine Oil Pressure Too Low Causes and Fixes

What's Unique About the 2021-2021 Ram 1500

On the 2021 Ram 1500, the cause of P0524 is highly dependent on the engine. For the 3.0L EcoDiesel, Ram has issued TSB #18-028-21 indicating the code can be triggered by software sensitivity in cold weather, often requiring a PCM update rather than a mechanical repair. Additionally, the EcoDiesel's cartridge-style oil filter is very sensitive; if the cap is not torqued to the specified 25 N·m (18 ft-lbs), it can cause a pressure drop and trigger the code, a common issue reported by owners after an oil change. For the popular 5.7L HEMI engine, a faulty oil pressure sensor is a very common failure point that can trigger this code even when the actual oil pressure is normal.

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 is on
• Low oil pressure warning light or message illuminated on the dashboard
• Engine making knocking, ticking, or rattling noises
• Poor engine performance, hesitation, or stalling
• For 5.7L HEMI, the Multi-Displacement System (MDS) may be disabled

Most Likely Causes

🎬 Watch: How to replace the oil pressure switch on a 5.7L HEMI." loading="lazy" style="max-width:100%;height:auto;border-radius:6px;display:block;box-shadow:0 2px 8px rgba(0,0,0,0.1);" />

1. Faulty Engine Oil Pressure Sensor 🔴 High Probability This is a historically common failure part on Ram/Chrysler engines, especially the 5.7L HEMI. The sensor can fail and send an incorrect low-pressure signal to the PCM, or get stuck at a certain reading.
   How to confirm: Verify actual oil pressure with a mechanical gauge. If the mechanical gauge shows good pressure (e.g., ~30 PSI at hot idle, 50-60 PSI at highway speed for a HEMI) but the code persists, the sensor or its wiring is faulty. A scan tool can also check the sensor's voltage with the Key On, Engine Off (KOEO); a reading near 0.27V is normal, while a reading near 4.89V indicates a failed sensor.
   Typical fix: Replace the engine oil pressure sensor. On the 5.7L HEMI, it is located on the engine block, just above the oil filter. Inspect the connector for oil contamination or damage.
   Est. part cost: $30-$80
2. Low Engine Oil Level 🔴 High Probability
   How to confirm: Check the engine oil dipstick when the vehicle is on level ground and the engine has been off for at least 5 minutes to allow oil to drain back to the pan.
   Typical fix: Add the manufacturer-specified engine oil (e.g., 5W-20 for HEMI, 5W-40 Synthetic for EcoDiesel) to bring the level to the 'Full' mark.
   Est. part cost: $10-$50
3. PCM Software Calibration Issue (3.0L EcoDiesel) 🟡 Medium Probability Manufacturer TSB #18-028-21 explicitly states that P0524 can be set on 3.0L Diesel models due to software sensitivity, especially on cold starts. This TSB addresses multiple potential codes and drivability issues.
   How to confirm: A Ram dealership can check if your vehicle's VIN is covered by TSB #18-028-21 and if the software update has been performed. This is especially likely if the code appears only in cold weather.
   Typical fix: Reprogram the Powertrain Control Module (PCM) with the latest available software at a dealership.
   Est. part cost: $0 (if under warranty) - $200
4. Incorrect Oil Viscosity or Clogged/Improperly Installed Oil Filter 🟡 Medium Probability → Shop Engine Oil Filter Adapter Using oil that is too thick for cold weather can cause a temporary drop in pressure at startup. For the 3.0L EcoDiesel, an improperly seated or over/under-torqued oil filter cap is a very common cause of P0524 immediately following an oil change. For the HEMI, low-quality aftermarket oil filters have been known to cause pressure issues, even when new.
   How to confirm: Verify the oil viscosity grade on your last service receipt matches the owner's manual. For EcoDiesels, remove and reinstall the oil filter cartridge, ensuring O-rings are lubricated and the cap is torqued to exactly 25 N·m (18 ft-lbs). If the code appeared after an oil change on a HEMI, replacing the filter with a quality OEM Mopar filter is a valid diagnostic step.
   Typical fix: Perform an oil and filter change using the correct OEM-specified oil and a high-quality filter (Mopar is recommended). Ensure correct installation procedures are followed precisely.
   Est. part cost: $50-$120
5. Failing Oil Pump or Clogged Pickup Tube ⚪ Low Probability → Shop Engine Oil Pump This is less common on newer vehicles but can occur due to engine sludge from poor maintenance or a manufacturing defect.
   How to confirm: This is diagnosed after confirming all the above causes are not the issue. A mechanical gauge will show consistently low pressure that does not rise appropriately with RPM. The oil pan must be removed to inspect the pickup tube screen and pump.
   Typical fix: Replace the engine oil pump and clean the oil pickup tube screen.
   Est. part cost: $150-$400

Rare But Worth Checking

• Worn Internal Engine Components: If the engine has high mileage or a history of poor maintenance, worn main bearings or camshaft bearings can cause a loss of oil pressure. This is a worst-case scenario requiring an engine rebuild or replacement. A mechanical gauge showing low pressure that doesn't improve with a new pump would point to this.
• Damaged Wiring to Oil Pressure Sensor: The wiring harness leading to the sensor can become damaged from heat or abrasion, causing a short or open circuit that mimics a sensor failure. Inspect the harness visually and check for continuity. The 3-pin connector pigtail is available as a separate part (Mopar #68334877AA) if the connector itself is damaged.

Diagnosis Steps

1. IMMEDIATELY turn off the engine to prevent damage.
2. Check the engine oil level using the dipstick. Top off if low with the correct oil type.
3. Verify that the correct viscosity engine oil was used during the last oil change. Consult the owner's manual (5W-20 for HEMI, 5W-40 synthetic for EcoDiesel).
4. For 3.0L EcoDiesel models, especially if the code appeared after an oil change: Remove the oil filter cap, check that the O-rings are present and lubricated, and reinstall, torquing the cap to exactly 25 N·m (18 ft-lbs).
5. CRITICAL STEP: Connect a mechanical oil pressure gauge to the engine to measure the actual oil pressure. This will determine if you have a real pressure problem or a sensor/electrical problem. Normal pressure for a warm 5.7L HEMI is around 30-35 PSI at idle and 50-65 PSI at highway speeds. For the 3.0L EcoDiesel, expect 17-23 PSI at hot idle.
6. If mechanical pressure is good: The issue is electrical. Inspect the oil pressure sensor's wiring and connector for damage or oil saturation. If the wiring is good, replace the engine oil pressure sensor.
7. If mechanical pressure is low: The issue is mechanical. Start with the cheapest fix: change the oil and filter using high-quality, OEM-spec parts. If pressure remains low, the oil pan must be removed to inspect the oil pickup tube for blockage. If the tube is clear, the oil pump is the likely culprit and should be replaced.
8. For 3.0L EcoDiesel models: If the code appears primarily during cold starts and the filter is correctly installed, contact a Ram dealer and reference TSB #18-028-21 to check if a PCM software update is available for your vehicle.

Parts You'll Likely Need

• Engine Oil Pressure Sensor/Switch (OEM #68212138AA (For 5.7L HEMI, verify by VIN)) — This is the most common point of failure, especially on HEMI engines. It sends an incorrect signal to the computer, triggering the P0524 code despite healthy oil pressure.
  Trusted brands: Mopar, Standard Motor Products (SMP), NTK
  OEM price range: $50-$90
  Aftermarket price range: $30-$60
• Engine Oil and Filter (OEM #Filter: MO-339 (5.7L HEMI), 68507598AA (3.0L EcoDiesel)) — Low oil level or using the wrong viscosity oil are common triggers. A low-quality or defective oil filter can also cause a pressure drop and trigger this code, even if newly installed.

Related Codes That Often Appear With This One

• P249C-00 — This code, 'Excessive Time To Enter Closed Loop Reductant Injection Control', is listed alongside P0524 in TSB #18-028-21 for the 3.0L EcoDiesel, suggesting a related software issue that can be fixed with a PCM flash.
• P02E8-00 — Also listed in TSB #18-028-21 for the 3.0L EcoDiesel, 'Diesel Intake Air Flow Position Sensor Circuit Low', indicating a potential group of codes that can be resolved with a PCM software update.
• P0520 — This code indicates a general fault in the oil pressure sensor circuit ('Engine Oil Pressure Sensor/Switch Circuit'). It can appear with P0524 as the PCM may identify both a general circuit malfunction and the specific 'too low' condition.
• P1524 — A related but distinct code for 'Oil Pressure Out of Range, Camshaft Advance/Retard Disabled'. It often appears on HEMI engines when oil pressure is too low to operate the MDS, and can be caused by the same faulty sensors or clogged filters.

Technical Service Bulletins (TSBs) & Recalls

• 18-028-21: Addresses P0524 on 2021 Ram 1500 3.0L Diesel models, specifically noting low oil pressure during cold starts, among other DTCs, fixable with a PCM software update.
• 18-008-21: A similar bulletin for 2020 Ram 1500 3.0L Diesel models that also lists P0524 in cold temperatures as a condition that can be fixed with a PCM reflash.
• 09-005-20: Outlines the correct oil filter change procedure for the 3.0L Diesel engine and explicitly states that P0524 may be set if the oil filter cap is not tightened to 25 N·m (18 ft-lbs).

Platform-Specific Known Issues

• A Ram Technical Service Bulletin (TSB #18-028-21) was issued for 2021 Ram 1500 models with the 3.0L EcoDiesel engine. It notes that P0524 can be set during start-up in cold weather and may be resolved by reprogramming the PCM with updated software.
• For the 3.0L EcoDiesel, TSB #09-005-20 warns that failure to properly tighten the oil filter cap to 25 N·m (18 ft-lbs) can cause the P0524 code to set. This is a very common user-error-induced fault.
• Numerous owner reports on forums like 5thgenrams.com confirm that for the 3.0L EcoDiesel, a low oil pressure warning after an oil change is almost always due to the oil filter cap not being fully seated or torqued down correctly.

Mechanic-Grade Diagnostic Values

• Oil Pressure Sensor Voltage (Key On, Engine Off) — expected: ~0.27 Volts. Failure: A reading near 5V (e.g., 4.89V) indicates a sensor that has failed and is stuck in a high reading state.
• 5.7L HEMI Mechanical Oil Pressure (Warm Engine) — expected: Minimum 4 PSI at idle; 25-110 PSI at 3,000 RPM.. Failure: Pressure below these service manual specifications indicates a mechanical issue.
• 3.0L EcoDiesel Mechanical Oil Pressure (Warm Engine) — expected: 17-23 PSI at hot idle; 30-40 PSI at highway speed.. Failure: Pressure consistently below these ranges indicates a potential mechanical issue.

Scan Tool Commands That Help

• wiTECH (Dealer Tool): Flash PCM with updated software — This is the specific fix mandated by TSB #18-028-21 for 3.0L EcoDiesel models that set P0524, particularly on cold starts, to correct software sensitivity.
• High-End OBD-II Scanner (e.g., Autel, iCarsoft): ECU Sync / Recalibration — Some scanners offer a function to recalibrate or sync the new oil pressure sensor with the ECU after replacement, which can help prevent the code from returning.

Wiring & Ground Locations

• Oil Pressure Sensor Connector — On the 5.7L HEMI, the sensor is on the front of the engine block, passenger side, located directly above the oil filter housing.. This 3-pin connector's wiring can be damaged by heat or abrasion, and the connector itself can become contaminated with oil, causing a faulty signal that triggers P0524. The pigtail is replaceable under Mopar part number 68334877AA.
• Sensor Circuit Ground — The specific ground point (G-point) for this circuit is not explicitly identified in public-facing documents, but it is part of the main engine harness.. A poor ground connection for the sensor circuit can cause incorrect voltage readings at the PCM, mimicking a sensor failure. If a new sensor doesn't fix the issue and mechanical pressure is good, checking the harness ground is a valid next step.

Real Owner Repair Stories

• RamForum.com user 'ShotgunWillie' (2013 Ram 1500 5.7L HEMI) — Check Engine Light with codes P1524 and P0521. Low oil pressure on dash gauge (25psi idle, 30psi highway).
  ❌ Tried (didn't work) Initial diagnosis pointed towards a bad sensor.
  ✅ What actually fixed it A shop confirmed the sensor was reading the actual low pressure. The cause was a cheap, recently installed 'Prompto' aftermarket oil filter restricting flow. An oil and filter change with a quality filter restored pressure to normal (35psi idle, 60psi highway) and cleared the codes.
• 5thGenRams Forum user (2019 Ram 1500 Rebel 5.7L) — Check Engine Light with code P1524.
  ❌ Tried (didn't work) Draining the oil (it looked fine).
  ✅ What actually fixed it The owner replaced the oil filter. This alone solved the problem and the code did not return, suggesting the previous filter was faulty or restrictive.
• RamForum.com user 'Hemi450' (2011 Ram 1500 5.7L Hemi) — P0524 code (Low Oil Pressure) kept appearing after a new engine installation.
  ❌ Tried (didn't work) Resetting the code. The code would always reappear.
  ✅ What actually fixed it This case was unresolved but presented a unique problem. The owner had installed a high-volume SRT oil pump and confirmed with a mechanical gauge that the pressure was very high (38 psi hot idle). The P0524 code persisted, leading to the theory that the pressure was outside the PCM's expected range, or the new pump had the wrong internal bypass spring, causing the computer to set a fault code.

"I Checked Everything" — The Actual Cause

• The equivalent for P0524 is when a mechanical oil pressure gauge confirms pressure is good, but the code persists. In these cases, the cause is almost always electrical. A technician on a forum confirmed that checking the oil pressure sensor's voltage with the key on, engine off (KOEO) is a definitive test; a normal reading is ~0.27V, while a failed sensor often reads high, near 4.89V, directly pointing to a bad sensor despite good mechanical pressure. If the sensor and its voltage test good, the next step is to inspect the wiring harness and its ground connection for faults.