Definition of Code P0925
The diagnostic trouble code P0925 detects a problem with the gear shift reverse actuator circuit.
What does code P0925 mean?
Code P0925 is a generic OBD-II trouble code that indicates an issue with the transmission reverse gear actuator circuit. The gear shift reverse actuator is responsible for shifting the transmission into reverse. When the Powertrain Control Module (PCM) or Engine Control Module (ECM) detects an abnormal voltage reading in the gear shift reverse actuator circuit, the P0925 trouble code will be triggered.
What causes code P0925?
Several different issues can lead to the P0925 trouble code being triggered:
- Faulty reverse gear actuator
- Mechanical problems in the transmission
- Defective reverse guide rail or shift shaft
- In rare cases, a faulty PCM, ECM, or transmission control module
- Damaged electrical components in the system, such as shorted wires or corroded connectors
What are the symptoms of code P0925?
The P0925 trouble code will likely be accompanied by the Check Engine light illuminated on the instrument cluster. The vehicle will also likely have trouble shifting into or out of reverse, or may refuse to do so entirely. Reduced fuel efficiency is also common.
How does a mechanic diagnose code P0925?
Code P0925 will be diagnosed using a standard OBD-II trouble code scanner. A reputable technician may use the scanner’s freeze frame data to assess the P0925 code and also look for any additional trouble codes that are present. If multiple codes are present, they should be addressed in the order they appear. The mechanic will then reset the trouble codes, restart the vehicle, and check if the code returns. If the P0925 code disappears, it was likely triggered incorrectly or represents an intermittent issue.
If the code returns, the mechanic should begin with a visual inspection of all electrical components in the system. Any damaged wires, connectors, fuses, or circuits will need to be replaced. Next, the mechanic will perform a thorough inspection of the gear shift reverse actuator, as well as the guide rail and shift shaft.
If the issue is still not resolved, a more in-depth inspection of the entire transmission system will be necessary.
Whenever a component is replaced during inspection and repairs, the mechanic should reset the trouble codes and restart the vehicle to see if the code returns. By doing this, the mechanic can know as soon as the problem is fixed.
Common mistakes when diagnosing code P0925
The most common mistake when diagnosing code P0925 comes from not following the OBD-II trouble code diagnostic protocol. Mechanics must adhere to the step-by-step protocol at all times to ensure their inspection and repair are as effective and efficient as possible. Failing to do so can result in addressing codes in the wrong order, missing a relatively simple fix, or not clearing the codes.
How severe is code P0925?
A vehicle with the P0925 trouble code can still be driven, although reverse gear may not be usable. If the car is driven with a detected P0925 code, severe transmission damage is at risk. For both of these reasons, the code should be addressed as soon as it is detected.
What repairs can fix code P0925?
Some repairs for code P0925 include:
- Replacing the gear shift reverse actuator
- Adjusting or replacing the reverse guide rail or shift shaft
- Replacing electrical components in the system
- Replacing the PCM, ECM, or transmission control module