Car Troubleshooting: Automatic Transmission Changing Gears

If your car’s automatic transmission is not changing gears properly, it can be a frustrating and potentially dangerous problem. There are a few common causes of this problem, and some of them can be fixed with simple maintenance. However, in some cases, you may need to have the transmission repaired or replaced.

Causes of an Automatic Transmission Not Changing Gears

1. Low Transmission Fluid

The transmission fluid is essential for the proper functioning of an automatic transmission. It lubricates the moving parts and helps to transfer power from the engine to the wheels. If the transmission fluid is low, it can cause the transmission to slip and not change gears properly.

2. Dirty Transmission Fluid

Over time, the transmission fluid can become dirty and contaminated with metal shavings and other debris. This can cause the transmission to shift hard or not change gears at all.

3. Faulty Solenoids

The solenoids in an automatic transmission are responsible for controlling the flow of transmission fluid. If a solenoid fails, it can prevent the transmission from changing gears properly.

4. Faulty Torque Converter

The torque converter is a fluid coupling that connects the engine to the transmission. If the torque converter fails, it can prevent the transmission from changing gears properly.

5. Faulty Transmission Control Module (TCM)

The TCM is the computer that controls the automatic transmission. If the TCM fails, it can cause the transmission to shift erratically or not change gears at all.

How to Fix an Automatic Transmission Not Changing Gears

1. Check the Transmission Fluid

The first step in fixing an automatic transmission that is not changing gears is to check the transmission fluid. The fluid should be at the correct level and should be clean and free of debris. If the fluid is low, add more fluid until it reaches the correct level. If the fluid is dirty, you may need to have the transmission flushed and refilled.

2. Replace the Transmission Solenoids

If the transmission fluid is clean and at the correct level, but the transmission is still not changing gears properly, you may need to replace the transmission solenoids. The solenoids are relatively inexpensive and easy to replace.

3. Replace the Torque Converter

If the transmission solenoids do not fix the problem, you may need to replace the torque converter. The torque converter is a more expensive and difficult part to replace, but it may be necessary to get your transmission working properly again.

4. Replace the Transmission Control Module (TCM)

If the torque converter does not fix the problem, you may need to replace the transmission control module (TCM). The TCM is a complex and expensive part to replace, but it may be necessary to get your transmission working properly again.

Preventing Automatic Transmission Problems

The best way to prevent automatic transmission problems is to perform regular maintenance. This includes checking the transmission fluid level and condition, and having the transmission serviced according to the manufacturer’s recommendations. You should also avoid driving aggressively, as this can put stress on the transmission.

If you experience any problems with your automatic transmission, it is important to have it diagnosed and repaired as soon as possible. Ignoring a transmission problem can lead to more serious damage and expensive repairs.