Transmission control modules (TCMs) are devices that directly control the speed and power of a car’s transmission. The purpose is to maximize efficiency while maximizing the strength of the wheels. In newer cars, they are built into the computer inside each vehicle.
Unfortunately, when these transmission control modules go bad, they can cause an erratic and unreliable shifting process and a severe engine check error.
To reset the transmission control module, first, you need to identify which TCM is the faulty one.
So when the transmission suddenly slips, you might know what you should do to help fix it. If not, these steps can still save your day and your car from significant potential damage.
- The first step is to turn the AC off and move the shifter to the park position.
- Next, make sure to turn off the ignition and wait for five to ten seconds.
- Now start the engine and allow it to idle for a few seconds.
- Now turn the ignition off and wait for another thirty to forty seconds.
- Keep doing these steps two to three times to reset the module.
But if you notice that still, it is not your transmission control module is not working correctly.
It is time to take the help of a professional as they will be able to diagnose the problem and reset or reprogram the module if needed.
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How Do You Check A Transmission Control Module?
There are several signs and symptoms which can tell you whether your transmission is going bad. Thus if you stay alert to these signs and would reset or replace the transmission module before it damages other components of the car would be beneficial for you.
So here are the five signs: difficulty in changing gears, poor fuel economy, delayed shifting, stuck in the same gear, or unpredictable shifting of gears.
- Difficulty changing into higher gears
If you find it challenging to shift higher gears, the problem is in your transmission module. The automatic gearbox carries the load through four different gears when you shift.
If you notice shifting into higher gears becomes problematic, then there should be something wrong with that transmission module. For this, you have to change or replace its transmission module and clear the error is made.
- Poor fuel economy
This is a common problem with all vehicles which have automatic gearboxes and are automatic transmissions as they take a lot of petrol to run smoothly and efficiently.
Therefore, the best way to check if your vehicle has a faulty transmission would be to check the car’s fuel economy.
If you find it is decreasing, then that would indicate your transmission is not working, due to which you should check whether there is something wrong with it or not.
- Delayed shifting
The most common problem with automatic transmissions is delayed shifts or poor shifting capabilities, which can be solved by changing the transmission module. If you find your car is not shifting instantly, the problem lies with the transmission.
The first sign of this would be that you find yourself downshifting even though you are not at high speed. It is troubling for people sitting in the car and those sitting in the front seats as they feel every time, such as jerky and rough start.
- Stuck in the same gear
This happens when it does not shift gears into a particular gear or keeps going into one of the gears instead of shifting to another one. Again, this would disturb you if you are driving long distances and would like to change your speed frequently.
Things will worsen if you notice that the car can no longer shift into any particular gear. It would be difficult for you; instead of shifting up or down, it would not be able to shift even at a low speed.
When your car does not want to pick up any of the gears, it means there is something wrong with the transmission module, and you should check it out.
So these are some of the signs and symptoms that you can look out for if you do not have experience with a car and can take your car to a mechanic to fix the problem.
What Causes A Transmission Control Module To Fail?
There are several reasons for your transmission control failing, and it could be anything from fault in the TCM Circuit board to the regular wear and tear of the components of the module.
The transmission control module can also be damaged by the heat coming from the engine. Thus today, you will know some of these causes of transmission control module failure in brief.
1. Faulty wiring in TCM circuit boards
It is very common in most vehicles. Starting with the wiring getting loose in the connections made and by the time it has got worse and real loose after some time.
2. Voltage gone to TCM circuit board
This is a major reason behind transmission control module failure. For example, sometimes, if you check at soft start, the transmission will be going up and down during starting of your car; this is because of voltage going to ICs of TCM faulty wiring or a burnt-out relay.
3. Heavy vibrations
The heavy vibrations will crush the components of TCM.
The heat produced by the engine will cause the meltdown of some electronic components in the TCM circuit board, which is a common reason for transmission control modules to go bad.
5. Mechanical consequences
If there is no voltage supplied to TCM, then it won’t start working, its active components will not get what they require, and due to this, the TCM Circuit board fails too.
6. Faulty solenoid
Faulty solenoid coils inside the TCM circuit board will be noticed by irregular starting gear shifting, flat spots, abrupt acceleration during driving, etc. So is one of the major reasons transmission control modules go bad.
If any faulty or loose connection is found in the solenoid or any of its parts, it will harm the transmission control module and may fail.