How Do You Reset an Engine Control Module? Location & Procedure

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As the owner of a gas-powered car, chances are you had to get your engine checked at least once. Transmission issues can be expensive to fix, and it’s surprisingly common that a simple problem with a ‘check engine light will lead to a much more costly repair. Of course, there are car repairs that you can do yourself. Transmission issues are typically one of them.

Let us tell you that the transmission control module (TCM) is a device that sends signals to your car’s transmission for it to function correctly. The number of parts that can go wrong with this device is high, but all of them are essential to the proper function of your vehicle. The transmission control module can stop working if it becomes dirty, corroded, or damaged.

4l80e control module

So now the question is, how can you reset the TCM? Keep on reading to find out!

How Do You Reset A Transmission Control Module?

Not everyone knows this, but there is a way to reset your transmission control module (TCM) without having to go into the car’s computer. It is especially useful for re-setting the “adaptive memory” in some transmissions, which you can’t do while driving because certain things must be done while coasting up to speed in neutral.

Of course, every car is different so this process might vary slightly from one to another. Consult the documentation for your specific vehicle if necessary.

Tools Needed

  • Multimeter
  • Helper


  1. The first thing you have to do is disconnect the negative/ground cable from the battery. You must do it to avoid an electrical shock while working near the car’s computer later on if your hands should slip.
  2. Remove the car’s positive (red) cable from the battery, then disconnect it at the starter solenoid if that was not where you disconnected it before.
  3. Pull out or unplug the car’s transmission control module. In some vehicles, it may be behind the glove box. In others, it will be under the passenger seat or on the driver’s side front edge of the engine compartment.
  4. Locate a gray wire with a black/white stripe on the TCM harness connector (or whatever color combination your car uses). The “signal” wire controls whether or not your vehicle enters fail-safe mode when placed into Park or Neutral from any other selector position.
  5. Connect your multimeter to this wire and ground it. Now put your transmission selector into P (Park if you’re using an automatic) or N (Neutral if you’re using a manual). If the multimeter reads anything lower than 11 volts, then your vehicle should now be ready to be put into fail-safe mode.
  6. Start the car by connecting the battery cables in reverse order of what you did before, and leave it running for 15-20 seconds. It will give it enough time to complete whatever task is necessary for entering fail-safe mode.
  7. Turn off your engine and disconnect the battery cables again, leaving them disconnected this time. Also, remember to re-connect/replace your TCM’s signal wire connector so that everything looks like no one ever touched it.
  8. The key back into your ignition and try to start the car again. 
  9. You should have reset your TCM by now, and your transmission should normally be working.

Check Out How To Reset All ECU’s and Control Modules in your Car or Truck:

YouTube video

4l60e Transmission Control Module Location

The transmission control module is a vital component under the hood of your car. This box regulates how efficiently fuel from an engine goes into its gears. Also, it contains sensors to detect any issues with this process before they become a big problem.

4l60e Transmission Specification

transmission problems

The 4L60E transmission provides electronic controls for operating the four-speed automatic electronically controlled transmission. The transmission features an aluminum case and an aluminum bell housing with lightweight steel rotor assemblies.

Functionally, it is similar to the 4L80E but has several important differences that affect its torque capacity. The 4L60E has a 50 percent higher torque rating than the 4L60. It is due to differences in materials, case design, and rotor support bearings.

4l60e Transmission Identification

There are many types of transmissions in vehicles. For example, a car might have a standard five-speed manual transmission or an automatic four-speed. A truck may have a six-speed manual while another has a two-speed automatic. 

Larger trucks often have 9 to 18 speeds and differentials and other devices, making them even more complicated. If you work on a vehicle, it will be much easier to know what type of transmission it has and how it is operated.

Four-Speed Manuals

These transmissions have four forward speeds plus reverse, clutches, and a three-speed auxiliary section known as the “Low Gear.” The main controls are a clutch pedal, three-shift levers, and four electrical switches on the dashboard.

The simplified controls get added to the system through a transmission range selector. It has a cable that runs to the shift selector in the transmission. A lock-up control solenoid is installed, which locks up the torque converter on the 3rd and 4th gear for better performance.

Three-Speed Automatics

These transmissions have three forward speeds plus reverse, with the torque converter supplying extra ‘gear’ ratios. The main controls are two pedals, a selector lever in the center of the floor, and three electrical switches on the dashboard. Each selector can move fore and aft into neutral than either of the “Drive” positions. 

The vehicle will have an easy-starting push-button electric starter, automatic choke, accelerator pedal with a return spring, kick down switch in the transmission range selector, plus an engine starter solenoid that gets energized in “Park” or “Neutral” mode.

What Are The Signs Of A Bad Transmission Control Module?

Several warning signs can help determine if your transmission control module needs replacement. Here are the most common signs:

1. Transmission slips while driving

If your car suddenly starts to slip while driving, this could be a sign of a problem with the transmission control unit. If you noticed other issues with your vehicle before or after the slipping event, this is a sure sign that you will need to replace it.

2. Transmission does not engage

The transmission control module controls when your vehicle shifts gears. If you notice that your car is no longer shifting into higher gears and suddenly begins to slip, there may be a problem with your transmission control module. 

3. Transmission fluid discoloration

If your transmission fluid is becoming discolored, this may be due to overheating in the transmission control module or other components in the transmission system. It usually happens because of a clogged transmission filter screen. If you see any signs of overheating or transmission fluid discoloration, you should replace your transmission control module as quickly as possible.

4. Transmission shifting problems

If the transmission in your car is not shifting between gears properly, then it also indicates a faulty TCM. If there is visible evidence of damage to the components of the automatic gearbox, it’s time to repair or replace the transmission control module.

5. Communication problems with the engine and transmission control modules

If your car suddenly has trouble communicating with one of the two modules, you should get an experienced mechanic to check the other one as soon as possible. This miscommunication can lead to problems with your car’s shifting. These problems may include slipping, difficulty shifting into higher gears, or sudden stalling.

6. TCM warning light is on

There is a problem if the TCM warning light or engine malfunction indicator light suddenly shows up. This light can indicate problems with your vehicle’s wiring or electrical components. If you have problems with any of these parts, it will usually require replacing the entire control module.

7. Transmission performs erratically

If your car performs erratically, this could be due to an improper shift from the transmission control module. Also, it can be due to an electrical problem, which will usually result in the transmission control module needing replacement. You may also notice problems with shifting or slipping after long periods of idling or slow speeds.

A bad transmission control module can have very serious consequences. So, if you are experiencing any of these issues, make an appointment with your mechanic as soon as possible. If your car still has a valid warranty, it will cover the repairs or replacement costs.

Check Out Symptoms of a Bad Transmission Control Module:

YouTube video

How Much Does It Cost To Fix A Transmission Control Module?

Several components can go wrong with your car’s transmission control module. Each part is unique, and going to the right service center for the necessary repair is crucial to avoid a sloppy job. It can lead to a very expensive repair, but there is a way to prevent the mechanic’s steep costs.

Replacing the module can be a real headache because there are different modern cars. Even multiple modules go into one car depending on its make and model! Because of this, replacement parts can quickly add up to an astronomical sum when you don’t have to pay for them.

Your best bet is to take your car to an authorized service center and have the manufacturer diagnose the problem with your car’s transmission control module. It will help you avoid paying too much for repairs or having to spend money on replacement parts that will cost more than the module itself. If you own a new car, this may be the only way to get warranty coverage for this problem.

Trick To Save Money On Repairs

To avoid paying a lot for repairs, make sure you choose a part your warranty covers or comes from your car’s manufacturer, such as Ford or Honda. Check alternative shops and suppliers like AutoZone or Advanced Auto Parts if you want to avoid paying an authorized dealer. 

Although they are often more expensive than independent shops, the labor costs at authorized shops are more expensive. If you can find a part that your warranty covers at an independent shop, you’ll save yourself a great deal of money.

Tips When Resetting A Transmission Control Module

The main objective of a transmission control module is to precisely provide the right engine changes to provide the optimum engine performance of the car.

  • You can reset it by taking off the position of its power supply for more than five minutes and then turning it on. 
  • It is possible to do it five times till the engine is thoroughly warm, but you should avoid it in low temperatures.
  • The transmission control module increases the car’s performance, so you should reset it after every six months. Some vehicles need resetting once every three months.
  • When the engine is cold, it takes five minutes to warm it up enough to perform at its optimum level. 
  • Turning off the car and removing the key from the ignition is enough to reset it. You can disconnect the battery for a few minutes and connect it back. However, the power supply should remain disconnected for five minutes in some cases.
  • After turning on the car, you must shift through the automatic transmission gear at least two times. 
  • In manual cars, shifting between drive and reverse should occur three times. The gear shifting must continue for at least 10 miles, and automatically reset the transmission control module.
  • You can turn off the module’s power supply by disconnecting its battery or by pulling out fuses from the fuse box. But in some cars, it has to be done by pulling out a relay connected to the module.

Reprogramming Transmission Control Module

Reprogramming your transmission control module might be the most important step to fixing the “check gauges” light. Over time, different factors can change the performance of your vehicle’s electrical system and impact your transmission. 

For example, if your car isn’t starting properly or getting fewer miles/gallon, your battery or alternator isn’t charging correctly. It can impact how the transmission shifts gears, resulting in a check gauge light.

Check Out GM TCM (Transmission Control Module) Programming (SPS1 Old system):

YouTube video

Does A Transmission Control Module Need To Be Programmed?

Transmission Control Modules are made by various companies but are essentially the same. If you have an aftermarket controller/module, it will have to be reprogrammed every time you replace the factory one.

It also ensures that you replace worn-out parts with new ones. The TCM will have to get reprogrammed for the car’s computer system to know that different components are installed rather than what it’s used to seeing. 

Additionally, if your vehicle is not thoroughly checked before reprogramming, you could end up damaging your new parts. Due to this, your car could end up in the shop again. It is why checking for proper function before adding new parts is very important.

How do I know if my TCM needs to be programmed?

If your TCM has failed and the check engine light is on, the chances are that you will need to get the engine control unit process reprogrammed. It is only a rule of thumb, as some people have replaced their TCMs without having them programmed and still have the check engine light on. 

If you replace your TCM without programming it, the diagnostic trouble codes will not be cleared from your engine control module after replacement. However, this does NOT mean that your car won’t run properly or smoothly without reprogramming. 

How Much Does It Cost To Reprogram Transmission Control Modules?

A dealer or an automotive locksmith can reprogram the transmission control module. The cost of this varies from around $70 to over $200, depending on the vehicle. For instance, a T-Mod on a 02 Chevy S10 Blazer costs around $140 and takes about 2 hours to complete. 

How Long Does It Take To Reprogram A Transmission?

how to clear transmission codes

The length of time it takes to reprogram a transmission varies depending on several factors.

  • First, it depends on the make and model of the vehicle. 
  • A transmission reprogramming also depends on where the vehicle is getting serviced. 
  • A car dealership would take less time than if you were to bring your car to an individual’s garage.

Reprogramming a car’s transmission can take anywhere from two to six hours. For older cars, it can take even longer than that. If you choose to bring your vehicle to a dealership, we recommend calling ahead of time and making an appointment.


Where is the location of the transmission control module?

The transmission control module is a small diagnostic computer that controls the operation of your automatic transmission. It is usually in one of the following three places.

1. Under the hood (in older models)
2. In the trunk (in some makes and models)
3. On the side of the transmission (in most newer models).

Will TCM be reset if the battery is disconnected?

Disconnecting the battery can cause issues and any other power disconnection. Disconnecting the battery will reset the TCM and erase all of your radio presets, clock, and door lock codes. 

Other modules, such as the powertrain control module (PCM), also need to be reset and reprogrammed if they experience issues, but disconnecting the battery will not reset these modules for you.

Will a malfunctioning transmission Throw a code?

In short, yes. It will be an “L” or an “R” code, meaning the car is pulling in one direction or the other. Now, because there are a lot of parts that work together to make your transmission run smoothly, there are a lot of things that can go wrong. 

A bad input shaft speed sensor (ISS) or torque converter can cause the car to skip gears. A bad transmission solenoid can affect shift points and pressures, causing the computer to see trouble where there is none. And a bad transmission can simply break in the middle of driving, stranding you on the side of the road.

Does a pre-owned TCM require programming?

No, you don’t need to reprogram used TCMs. When you try a used TCMs in the car, it’ll say “Drive Cycle Not Completed” or something along those lines. But, you don’t need to reprogram it after that. However, you will still have to complete the drive cycle on the used TCMs.

Final Considerations

If any signs of a faulty TCM are apparent in your car, it’s best to take it to an expert mechanic ASAP. He will diagnose the problem and repair it. The transmission control module controls all the transmission functions, so it’s vital that you promptly fix this problem.

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Matt's interest for vehicles began at an early age, inspiring his lifelong excitement for all things automotive. He embraces the virtual world to indulge in his automobile interest as an avid Gran Turismo player. His writing ability effortlessly brings to life intriguing stories and educational articles on everything car-related.

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