Hydraulic Pressure Unit Loss of Pressure
The P0944 code indicates that the powertrain control module (PCM) has detected a loss of pressure in the hydraulic pressure unit, which is typically part of the transmission or clutch system. This can be caused by low hydraulic fluid, a faulty pump, internal leaks, or electrical issues. The condition may lead to harsh shifting, slipping, or inability to move the vehicle.
01. Most Common Causes
- Low hydraulic fluid level
- Faulty hydraulic pump
- Internal hydraulic leak
- Clogged hydraulic filter
- Faulty pressure sensor or wiring
02. Symptoms You Will Notice
- Check Engine Light illuminated
- Harsh or delayed shifting
- Transmission slipping
- Vehicle may not move
- Unusual noises from transmission
03. Step-by-Step Diagnosis
Step 1: Check hydraulic fluid level and condition; top off or replace if necessary.
Step 2: Inspect for external leaks around the hydraulic unit and lines.
Step 3: Use a scan tool to monitor hydraulic pressure readings and compare to specifications.
Step 4: Test the hydraulic pump operation and pressure sensor with a multimeter.
Step 5: If no issues found, perform a hydraulic pressure test to identify internal leaks.
04. Commonly Affected Makes
05. Frequently Asked Questions
Is it safe to drive with this code?▼
No, driving with P0944 can cause transmission damage or complete failure. Have the vehicle towed to a repair shop.
How much does it cost to fix?▼
Costs vary from $50 for a fluid top-off to $150 for sensor replacement; major repairs like pump replacement can exceed $1,000.