How To Reset Transmission Control Module Chevy – Step By Step Guide

When it comes to maintaining your Chevy vehicle’s longevity and peak performance, understanding every component is essential. Among the various components in your Chevy, one stands out for its vital role – the Transmission Control Module (TCM). This guide has been prepared to help you master the process of resetting your TCM, emphasizing the importance of the task while highlighting key factors you need to be mindful of.

The TCM is essentially the brain of your vehicle’s automatic transmission. It receives and processes signals from various sensors in your vehicle and, in response, controls the operation of the transmission. These operations include when and how to change gears for optimal driving performance. A well-functioning TCM contributes to the smooth operation of your vehicle, affecting fuel efficiency, engine performance, and overall drivability.

This guide is particularly important for owners of Chevy vehicles as it is tailored to these models, ensuring accuracy and relevancy. By the end of this detailed walkthrough, you will have a clear understanding of the how, why, and when of resetting the transmission control module in your Chevy.

Step What To Do
1 Check the key position and ensure it is set to “2” without starting the engine.
2 Press and hold down the accelerator pedal all the way to activate the kick-down switch.
3 Keep the accelerator pedal depressed for approximately 15 seconds.
4 While still holding down the accelerator pedal, turn the key to the “Off” position.
5 Release the accelerator pedal.
6 Wait for about 5 minutes with the engine turned off.
7 Start the vehicle and take it for a test drive of approximately 20 minutes to allow the TCM and ECU to adapt to your driving patterns.

Symptoms of a Malfunctioning TCM

Before diving into the TCM resetting process, it’s important to know the signs of a bad Transmission Control Module. Recognizing these symptoms early can prevent further damage to your vehicle’s transmission system. A range of signs could indicate a malfunctioning TCM:

  1. Unpredictable Shifting Patterns: If your vehicle starts shifting gears unexpectedly or if the shifts seem inconsistent with your driving, it could indicate a failing TCM. This unpredictability can take many forms, from abrupt gear changes to shifts that don’t seem to sync with your driving style.
  2. Difficulties Shifting into Higher Gears: Another common symptom is the vehicle struggling or delaying shifting into higher gears. If your vehicle has trouble accelerating or maintaining high speeds, your TCM might be on the fritz. This is especially true if these symptoms occur despite good engine performance.
  3. Delayed Shifting and Downshifting Problems: You might notice a significant delay when shifting gears, or your vehicle may not downshift when you slow down or come to a stop. Both scenarios could indicate a problem with the TCM.
  4. Poor Fuel Economy: If your vehicle’s fuel efficiency drops significantly and inexplicably, a malfunctioning TCM could be the culprit. The TCM plays a significant role in optimizing fuel efficiency by ensuring smooth gear shifts. Therefore, a failing TCM can negatively impact the fuel economy.
  5. Check Engine Light: Last but not least, if the Check Engine Light illuminates, your TCM might be sending a distress signal. While many issues can trigger the Check Engine Light, a failing TCM is definitely among the potential causes.

More details about these symptoms can be found here.

Preparation for the Reset Process

Safety comes first when dealing with vehicle components, so make sure you follow the instructions accurately. Prior to the reset, check the key position. Changing the key position to 2 ensures the dashboard lights are on, which is vital for the process.

Key Positioning: This step may seem simple, but it’s crucial for the resetting process. Turn the key to the ‘2’ position, ensuring that the dashboard lights are illuminated. Remember, starting the car at this stage isn’t necessary. Be careful to set the ‘KEY’ to the correct position. You should hear two clicks, and the dashboard lights should come on, but do not start the engine yet.

More on preparation for the reset process can be found here.

How To Reset Transmission Control Module Chevy – Step By Step Guide

How To Reset Transmission Control Module Chevy

Once you’ve correctly positioned the key, it’s time to move onto the resetting process:

Step 1: Pressing the Gas Pedal: After completing the key positioning, press down on the accelerator pedal. Make sure to depress it all the way to activate the kick-down switch.

Step 2: Keep the Pedal Depressed: Continue to the next step while keeping the accelerator pedal depressed.

Step 3: Waiting: Wait for approximately 15 seconds. During this time, do not release the accelerator pedal.

Step 4: Turning the Key Off: Without releasing the accelerator pedal, turn the key to the ‘off’ position. It’s essential to maintain the pedal’s position throughout this step.

Step 5: Releasing the Gas Pedal: Only after turning the key off can you release the gas pedal.

Step 6: Waiting: Finally, wait for approximately 2 minutes with the engine off before restarting your vehicle. During this time, the TCM resets and is ready for a fresh start.

The complete details for the resetting process can be found here.

Final Steps and Test Drive

Upon successfully resetting the TCM, give your vehicle a bit of time. The TCM and ECU need a few moments to adjust and learn. This is where a test drive comes in. For about 20 minutes, drive your vehicle around, giving the TCU and ECU time to adjust to your driving patterns.

The full guide for the final steps can be found here.


1. What is the Transmission Control Module (TCM)?

The TCM is a vital component of your vehicle’s automatic transmission. It’s essentially the brain of your vehicle’s transmission system, controlling when and how gears change based on signals it receives from various sensors.

2. Why is resetting the TCM necessary?

Resetting the TCM is a helpful procedure when your vehicle is experiencing problems with gear shifts. It resets the TCM’s memory, allowing it to learn and adapt to your driving style, which can help to improve the smoothness of gear changes.

3. Can I perform the TCM reset myself?

Yes, it’s possible to reset the TCM yourself. This guide provides a step-by-step process to do so. However, if you’re uncomfortable performing the task or if the problems persist after the reset, it’s best to seek help from a professional.

4. How long does the TCM reset process take?

The actual reset process takes around 20 minutes, which includes the time for the initial reset and the subsequent test drive.

5. How often should I reset the TCM?

There’s no set frequency for resetting the TCM. It’s generally done when you notice problems with the transmission system, like rough or unpredictable gear shifts. However, if you notice such issues frequently, it might indicate a more serious problem that needs professional attention.


To wrap up, resetting the Transmission Control Module is an essential part of maintaining your Chevy’s performance. Throughout this guide, we’ve walked through how to recognize signs of a faulty TCM, steps to prepare for resetting, the resetting process itself, and the final steps to take post-reset. If you’ve followed this guide accurately, you should now have a reset TCM and a smoother driving experience.

However, we advise all readers to consult their vehicle’s manual or seek professional help when in doubt. It’s always better to seek professional advice if any issues persist or the symptoms worsen.

For more information on related topics, check out these articles on our blog:

  1. What does the VSA light on a Honda mean?
  2. What would cause the VSA light to come on?
  3. Idle air control valve stuck open symptoms

Remember, understanding your vehicle is the first step towards efficient maintenance and optimum performance. Happy driving!

Leave a Comment