Diagnosing Error Code P0933 in Automatic Transmissions: Gear Shift Problems

Automatic transmission problems can be intimidating, and for a good reason. The transmission is one of the most sensitive parts of your vehicle's engine, and improper maintenance can worsen the issues..

However, not every issue is catastrophic. The P0933 error code indicates a transmission problem, but quick response can make repairs easier and more affordable.

Understanding Error Code P0933

Any On-Board-Diagnostic message bearing the last three digits in the 900s means there’s something amiss with your transmission’s hydraulic pressure system.   Automatic transmissions rely on hydraulic pressure, which results from spinning fluid, to move the vehicle’s axle, thus enabling the driver to control steering.  One of the many parts of the hydraulic system is the pressure sensor—and that’s where the P0933 code comes into play.

On the 68RFE in Ram 2500 and 3500 trucks, P0933 often appears next to P0868, and the two point in different directions: P0933 at the sensor and its circuit, P0868 at the fluid supply. Our 68RFE low line pressure guide explains how to tell them apart.

Work of the hydraulic pressure sensor

Hydraulic pressure is the “muscle” behind an auto’s maneuverability and it’s one of several things that makes automatic transmissions possible.  But that pressure has to be balanced correctly in order to do its job right.

Too much pressure, and you risk damage to the seal or pump;  too little, and your gears will stick, grind, or jerk.  The hydraulic pressure sensor is what tells your car’s Transmission Control Module (TCM) what the pressure readings are so it can adjust accordingly. 

The device is either an internal part of the transmission unit, or it’s mounted securely on the side or the front of the vehicle, depending on the make and model.  A P0933 error code simply tells you that the sensor isn’t working right, or at all.

Signs of Hydraulic Pressure Sensor Malfunction

Like most transmission problems, your car will give you some early warning signals.  You may start to notice that the gears aren’t shifting smoothly—resulting in a jerky ride—or they may even be stuck.  And when the gears do change, they may be accompanied by grinding or moaning noises.   Your “check engine” light should also tell you there’s a problem.  When the car begins to seriously overheat and you detect a burning smell—it’s way past time to pull over and get it checked out.

Why Do Transmission Pressure Sensors Fail?

There can be multiple reasons for sensor failure, often related to electrical issues such as wiring shorts, TCM malfunctions, or faulty parts like the pump, solenoid, or the sensor itself.

Automatic transmissions operate as a system; a problem in any part can trigger a P0933 error code. A thorough diagnostic is needed to pinpoint the exact issue.

Finding the right solution starts with diagnosing the correct problem. Possible solutions include:

• Replacing faulty, frayed, or corroded wiring
• Replacing malfunctioning parts, such as the solenoid or the sensor itself
• nsuring the transmission fluid and filter are clean (a clog can sometimes send a false message)
• Examining the TCM for potential issues.

Whatever the issue, make sure you replace or repair parts or accessories with only the best quality products. Sun Transmissions is here to help you do just that.   

We’re standing by to talk with you about issues with your automatic transmission or power steering system and we’re ready to send you whatever you need.  Reach out to us today!