The world of cars is constantly changing and advancing, and one of the ways that advancements have been made is through the use of OBD-II codes. These codes, also known as diagnostic trouble codes, are used to identify issues within a car that need to be addressed. One of the codes that can come up is P28E4 – Shift Motor Driver Current/Temperature Too High. In this article, we will explore what this code means, possible causes, how to diagnose the problem, and how to repair it.
What is OBD-II Code P28E4 – Shift Motor Driver Current/Temperature Too High
The shift motor driver current/temperature too high code is a standard OBD-II code that indicates that the Engine Control Module (ECM) has detected a problem with the shift motor driver current and temperature in a transmission control module in a vehicle. The transmission control module is responsible for shifting gears in an automatic transmission. The shift motor driver is the component responsible for operating the shift motor, and the current and temperature levels should not exceed a certain range. If they do exceed this range, it will trigger this code. This code can refer to various shifting issues that the vehicle may be experiencing, so it is important to diagnose it correctly to avoid misdiagnosis and unnecessary repairs.
Possible Causes of the P28E4 Code
There are a number of reasons why this code may come up. Here are some of the most common causes of the P28E4 code:
1. Failure of shift actuator motor: The shift actuator motor in an automatic transmission is responsible for shifting gears, and if it fails, it can cause the P28E4 code to appear.
2. Problems with wiring: Wiring failures, including short circuits, open circuits, and resistance, can cause the transmission control module to malfunction. This can cause the shift motor driver current/temperature too high code to appear.
3. Transmission control module failure: The transmission control module can also fail and cause this code to appear.
4. Low transmission fluid: Low transmission fluid, or even old transmission fluid, can cause the transmission to work harder than usual and result in higher than normal working temperatures. This can cause the shift motor driver current/temperature too high code to appear.
5. Wrong type of fluid: Sometimes, the wrong type of transmission fluid can be added to a vehicle. This can cause the same side effects as low fluid levels and in the end, it can also cause the P28E4 code to appear.
Diagnosing the P28E4 Code
The P28E4 code can be diagnosed through a number of techniques. Here are some of the most common:
1. Use of an OBD code reader: The first step in diagnosing the P28E4 code is to use an OBD code reader. This can allow you to determine which code(s) are coming up and give you a general idea of where the problem might be. Once you have this information, you can begin to narrow down your diagnostic efforts.
2. Check the transmission fluid: Check the transmission fluid level. If it is too low or has not been changed in a while, it will need to be refilled or replaced.
3. Check wiring connections: Check the wiring for damage, and look for moisture that could be causing damage to the connections.
4. Resetting the code: If it is a new car (less than 10 years old), the P28E4 code can be reset to see if it appears again. If it does, then there may be an issue with the shift motor driver current and temperature.
5. Use of repair manuals: Repair manuals are an excellent resource that can be found online and in libraries. These manuals provide step-by-step instructions on how to diagnose and repair various issues in a car.
How to Repair the P28E4 Code
Once you have identified the cause of the P28E4 code, you can begin to repair it. Here are some of the most common repair techniques for this code:
1. Replacing the shift actuator motor: If the shift actuator motor has failed, it will need to be replaced. This will require removing the old motor and installing a new one.
2. Fixing the wiring: If there is an issue with the wiring, it will need to be fixed. This could include replacing any damaged wires, repairing any connectors, or even replacing the wiring harness altogether.
3. Repairing or replacing the transmission control module: If the transmission control module has failed, it will need to be repaired or replaced. This should be done by a mechanic who specializes in transmission repairs.
FAQ:
1. Can the P28E4 code be ignored?
No, it should not be ignored because it can lead to transmission problems in the future.
2. How much does it cost to replace the shift actuator motor?
The cost of replacing the shift actuator motor can vary depending on the make and model of the car and the location.
3. Will resetting the code fix the problem?
Resetting the code without fixing the underlying issue is not recommended, as the code will likely appear again in the future.
4. Can I still drive my car with the P28E4 code?
It is not recommended to continue driving your car if the P28E4 code appears because it can damage the transmission.
5. Can I diagnose and repair the P28E4 code myself?
While some minor repairs can be done on your own, it is best to seek the help of a professional mechanic to diagnose and repair the issue if you are not experienced with car repairs.
In conclusion, the P28E4 code indicates an issue with the shift motor driver current/temperature in the transmission control module. It can have various causes, including failure of the shift actuator motor, wiring problems, transmission control module failure, low transmission fluid, and wrong type of fluid. Diagnosing such a problem can be done through various techniques including OBD code readers, checking the transmission fluid, having an expert technician examine the wiring connections, resetting the code, and using repair manuals. Repairing the problem involves replacing the shift actuator motor or fixing the wiring, or repairing or replacing the transmission control module if the issue is diagnosed correctly. Finally, it is not recommended to ignore this code, continue driving if it appears, or diagnostic and repair it on your own without the supervision of a professional mechanic.