The P0944 trouble code is a diagnostic code that indicates a loss of pressure in the transmission’s hydraulic pressure unit. This code is commonly associated with automatic transmission systems and can lead to significant drivability issues if not addressed promptly. When your vehicle’s onboard computer detects a substantial drop in transmission pressure and determines that the hydraulic pump has lost its prime, it will trigger the P0944 code and illuminate the Check Engine Light.
| P0944 Code Meaning | P0944 Code Common Causes |
|---|---|
| Loss of hydraulic pump prime | Low transmission fluid level |
| Significant drop in transmission pressure | Faulty transmission pump |
| Failure of hydraulic pressure unit | Clogged or damaged transmission filter |
| Transmission pump prime test failure | Damaged internal seals |
| Hydraulic system malfunction | Worn or damaged transmission components |
Low Transmission Fluid Level
One of the most common causes of the P0944 code is a low transmission fluid level. Transmission fluid is crucial for maintaining proper hydraulic pressure within the system.
Symptoms
- Erratic shifting
- Slipping gears
- Overheating transmission
- Unusual noises from the transmission
Technical Explanation
Transmission fluid acts as both a lubricant and a hydraulic fluid. When the fluid level is low, the hydraulic pump may not be able to maintain the necessary pressure to operate the transmission effectively. This can lead to a loss of prime in the pump and trigger the P0944 code.
Step-by-Step Diagnosis
- Park the vehicle on a level surface and engage the parking brake.
- Locate the transmission dipstick (refer to your vehicle’s manual if unsure).
- Remove the dipstick and wipe it clean with a lint-free cloth.
- Reinsert the dipstick fully, then remove it again to check the fluid level.
- The fluid level should be between the “Full” and “Add” marks on the dipstick.
- Inspect the fluid color and smell. It should be red or pink and not have a burnt odor.
Solution
If the fluid level is low, add the appropriate type of transmission fluid as specified in your vehicle’s manual. Be careful not to overfill, as this can also cause issues.
- Use a funnel to add small amounts of fluid at a time.
- Recheck the level after each addition.
- Start the engine and let it run for a few minutes, then recheck the level.
- If the level was significantly low, inspect for leaks in the transmission system.
Cost Estimate
- DIY fluid top-up: $20 – $50 for transmission fluid
- Professional service: $50 – $100 for fluid check and top-up
Warnings and Recommendations
Warning: Using the wrong type of transmission fluid can cause severe damage to your transmission. Always use the fluid specified by your vehicle manufacturer.
If you’ve recently had transmission work done or notice puddles under your vehicle, have the system inspected for leaks before adding more fluid.
Faulty Transmission Pump
A faulty transmission pump is another common cause of the P0944 code. The pump is responsible for circulating transmission fluid and maintaining pressure within the system.
Symptoms
- Transmission slipping
- Delayed or harsh engagement of gears
- Whining or buzzing noise from the transmission
- Complete loss of drive in severe cases
Technical Explanation
The transmission pump creates the hydraulic pressure necessary for the transmission to function. When the pump fails or loses efficiency, it cannot maintain the required pressure, leading to a loss of prime and triggering the P0944 code.
Step-by-Step Diagnosis
- Connect a diagnostic scan tool to the vehicle’s OBD-II port.
- Clear the P0944 code and any other related codes.
- Test drive the vehicle to see if the code returns immediately.
- If the code doesn’t return, monitor transmission performance for any irregularities.
- If the code returns or symptoms persist, perform a transmission pressure test.
- Compare the pressure readings to the manufacturer’s specifications.
Solution
If the transmission pump is determined to be faulty, it will need to be replaced. This is a complex job that typically requires transmission removal and should be performed by a professional.
- Remove the transmission from the vehicle.
- Disassemble the transmission to access the pump.
- Replace the faulty pump with a new or remanufactured unit.
- Reassemble the transmission, ensuring all components are correctly installed.
- Reinstall the transmission in the vehicle.
- Refill with the correct type and amount of transmission fluid.
- Perform any necessary relearn procedures as specified by the manufacturer.
Cost Estimate
- Parts: $200 – $600 for the pump
- Labor: $500 – $1500 depending on the vehicle make and model
- Total: $700 – $2100
Warnings and Recommendations
Caution: Transmission repair is complex and requires specialized tools and knowledge. Improper repair can lead to severe transmission damage or failure.
Consider the age and overall condition of your vehicle when deciding whether to replace the pump or the entire transmission.
Clogged or Damaged Transmission Filter
A clogged or damaged transmission filter can restrict fluid flow, leading to a loss of hydraulic pressure and triggering the P0944 code.
Symptoms
- Delayed shifting
- Transmission overheating
- Jerking or shuddering during gear changes
- Metallic debris in the transmission fluid
Technical Explanation
The transmission filter removes contaminants from the fluid as it circulates. Over time, the filter can become clogged with debris, restricting fluid flow. In some cases, the filter may become damaged, allowing contaminants to pass through and potentially damage other transmission components.
Step-by-Step Diagnosis
- Check the transmission fluid level and condition.
- If the fluid is dirty or contains metal particles, the filter may be clogged or damaged.
- Remove the transmission pan to inspect the filter visually.
- Check for signs of damage or excessive debris buildup on the filter.
Solution
Replace the transmission filter and fluid if clogging or damage is found.
- Drain the transmission fluid into a suitable container.
- Remove the transmission pan, being careful not to damage the gasket.
- Locate and remove the old filter.
- Install the new filter, ensuring it’s properly seated.
- Clean the transmission pan and replace the gasket if necessary.
- Reinstall the pan and tighten the bolts to the manufacturer’s specifications.
- Refill the transmission with the correct type and amount of fluid.
- Start the engine and check for leaks.
Cost Estimate
- DIY: $50 – $150 for filter and fluid
- Professional service: $200 – $400
Warnings and Recommendations
Important: If you find metal particles in the old fluid or filter, this could indicate more serious transmission problems. Further inspection by a professional is recommended.
Always use a filter and fluid that meet your vehicle manufacturer’s specifications.
Damaged Internal Seals
Damaged internal seals within the transmission can lead to pressure loss and trigger the P0944 code.
Symptoms
- Fluid leaks
- Burning smell from the transmission
- Slipping gears
- Inconsistent shifting patterns
Technical Explanation
Internal seals in the transmission help maintain hydraulic pressure by preventing fluid from escaping designated passages. When these seals fail, pressure can be lost, leading to improper operation of clutches and bands within the transmission.
Step-by-Step Diagnosis
- Check for external transmission fluid leaks.
- Perform a pressure test on the transmission.
- If pressure is low in specific circuits, internal seal failure may be the cause.
- In some cases, a partial disassembly of the transmission may be necessary for a thorough inspection.
Solution
Replacing damaged internal seals typically requires transmission removal and partial or complete disassembly.
- Remove the transmission from the vehicle.
- Disassemble the transmission to access the damaged seals.
- Replace all worn or damaged seals.
- Inspect other components for wear while the transmission is disassembled.
- Reassemble the transmission, ensuring all components are correctly installed.
- Reinstall the transmission in the vehicle.
- Refill with the correct type and amount of transmission fluid.
- Perform any necessary adaptive learning procedures.
Cost Estimate
- Parts: $50 – $200 for seal kits
- Labor: $800 – $2000 depending on the extent of disassembly required
- Total: $850 – $2200
Warnings and Recommendations
Warning: Internal transmission repair is highly complex and should only be attempted by experienced professionals with the proper tools and knowledge.
Consider the overall condition of the transmission when deciding whether to repair or replace it, especially in older vehicles.
Worn or Damaged Transmission Components
In some cases, the P0944 code may be triggered by worn or damaged components within the transmission that affect hydraulic pressure.
Symptoms
- Rough shifting
- Transmission slipping
- Unusual noises during operation
- Inconsistent vehicle performance
Technical Explanation
Various components within the transmission, such as valve bodies, solenoids, or clutch packs, can wear over time. This wear can lead to internal leaks or improper operation, resulting in pressure loss and triggering the P0944 code.
Step-by-Step Diagnosis
- Perform a complete transmission scan using an advanced diagnostic tool.
- Analyze transmission data parameters for irregularities.
- Conduct a pressure test to identify areas of low pressure.
- Perform a transmission fluid analysis to check for excessive wear particles.
- In some cases, partial disassembly may be necessary for a thorough inspection.
Solution
The specific solution will depend on which components are worn or damaged. In many cases, a transmission overhaul or replacement may be the most cost-effective solution.
- Based on diagnostic results, determine which components need replacement.
- Remove the transmission from the vehicle.
- Disassemble the transmission and replace worn or damaged parts.
- Replace all seals and gaskets during reassembly.
- Reinstall the transmission in the vehicle.
- Refill with new transmission fluid.
- Perform any necessary adaptive learning procedures.
- Test drive to ensure proper operation.
Cost Estimate
- Partial rebuild: $1500 – $3000
- Complete transmission replacement: $3000 – $6000 (varies widely depending on vehicle make and model)
Warnings and Recommendations
Caution: Given the complexity and cost of major transmission work, get multiple professional opinions before proceeding with extensive repairs, especially on older vehicles.
Consider the overall condition and value of your vehicle when deciding between repair and replacement options.
In conclusion, the P0944 code indicates a serious issue with your vehicle’s transmission system that requires prompt attention. While some causes, like low fluid levels, can be easily addressed by DIY enthusiasts, many solutions require professional expertise and specialized equipment. Always prioritize safety and consult with a certified mechanic if you’re unsure about performing any diagnostics or repairs. Regular maintenance, including timely transmission fluid changes, can help prevent many of the issues that lead to the P0944 code.
Frequently Asked Questions About P0944
- Can I drive my car with the P0944 code?
It’s not recommended to drive with this code active. The transmission may fail unexpectedly, potentially leaving you stranded or causing an accident. - How urgent is it to fix the P0944 code?
Very urgent. This code indicates a significant transmission issue that can lead to complete transmission failure if not addressed promptly. - Will the P0944 code clear itself?
It’s unlikely. The code will typically remain until the underlying issue is resolved and the code is cleared with a scan tool. - How much does it typically cost to fix a P0944 code?
Costs can vary widely, from about $100 for a simple fluid top-up to $3000 or more for major transmission repairs or replacement. - Can a P0944 code be caused by electrical issues?
While less common, electrical problems like faulty sensors or wiring can sometimes trigger this code. A thorough diagnostic is necessary to rule out electrical causes. - Is the P0944 code specific to certain vehicle makes?
While it can occur in various vehicles, it’s most commonly associated with Chrysler, Dodge, and Jeep vehicles. - How long does it take to diagnose and repair a P0944 code?
Diagnosis can take 1-2 hours. Repairs can range from a quick 30-minute fluid top-up to several days for a full transmission rebuild or replacement. - Can I prevent the P0944 code from occurring?
Regular transmission maintenance, including fluid changes at recommended intervals, can help prevent many issues that lead to this code.