The engine control module has another name that is “Brain Box” because the engine control module or engine control unit controls your whole vehicle. It is so obvious that if you don’t know the right ECM replacement procedure, then you should not try to replace your ECM.
But, you don’t need to worry too much about ECM replacement procedures because now you know how to replace ECM, when to replace ECM and the right ECM installation process. Whether you want to reset your ECU or replace your ECM, you have to be more careful about the procedure. So, let’s see all of the ECM replacement procedures:
What Is The ECM And How Does It Work
The Engine Control Module is the main component that operates your vehicle at optimal performance. That’s why the ECM is popularly known for the car brain. The Engine Control Module (ECM) or Engine Control Unit (ECU) or Car Computer, whatever you say.
The ECM regulates lots of components in a vehicle, but the four main components the ECU maintains are idle speed, air-fuel ratio, ignition timing, and variable valve timing. So, it’s very understandable a car won’t be able to run properly without an Engine Control Module (ECM). The ECU takes data from the various sensors in the vehicle, and then by using this data, the ECM controls the whole vehicle.
ECM Replacement Procedure
When you want to know the right ECM replacement procedure, you have to know a little more about the Engine Control Module. Before replacing the ECM in the vehicle, you have to be certain and precise about what occurs in your ECM computer.
In the ECM replacement procedure, you will need to know what are the things to know before replacing your car ECM, Unnecessary return of your engine control module, why the ECM dies, and the ECM accurate identification. So the ECM replacement procedure is not only knowing the replacement process of ECM; it’s more than that.
But you won’t need to worry because I will show you everything you need to know about the ECM or ECU replacement procedure. To know the ECU replacement procedure, you should have to be practical because, with a better experience, you can understand the control unit properly.
How To Replace ECM Computer
To replace an ECM computer, you have to know the location of the Engine Control Module in your car. ECM location depends on your car model so, you have to know where your ECM is in your vehicle. After finding the ECM in your car to replace ECM will take a few more minutes.
ECM needs to be replaced for many causes but most of the common causes to replace the Engine Control Module computer is bad ECM in the car. At the same time, the ECM is the crucial component of a vehicle so, if there is anything wrong with it, you have to replace it as fast as you can. Before replacing the ECU computer, you should know the proper ECM replacement procedure.
Let’s see how to replace ECM step by step:
Step 1: Disconnect The Battery
Step 2: Locate The Engine Control Module (ECM)
Step 3: Disconnect The Electrical Supply
Step 4: Pull Out The Old or Bad ECM
Step 5: Insert The New ECM
Step 6: Bolt The ECM Place Tightly
Step 7: Connect The Electrical With ECM
Step 8: Reconnect The Battery Connection
Step 1: Disconnect The Battery
Whether you want to replace the ECM or reflash the ECM, you have to disconnect the battery connection in your vehicle before you take steps of the Engine Control Module installing procedure. Open up your car hood and the car engine compartment and disconnect the battery connection with a socket wrench.
Step 2: Locate The Engine Control Module
When you disconnect the battery, you open the engine compartment. So, now you just locate the ECM into the engine compartment. The location of an Engine control unit depends on the car’s model; some of the car’s ECM is located in the engine compartment, and others ECM computer in front of the seat in the car.
If you can’t find the ECM in your car, you should see your user’s manual, or you can ask for help from a car mechanic. Finding the Engine Control Module in your car won’t be that hard.
Step 3: Disconnect The Electrical Supply
Your car computer or ECM is connected with the vehicle’s electrical supply. To replace the ECM, you have to disconnect the electrical supply. Lift the locking tab of the electrical supply and pull away from the computer; this is the way how you can disconnect the electrical supply from the car Engine control unit.
Step 4: Pull Out The Old or Bad ECM
There must be a reason why you need to replace the ECM computer. Most commonly, car owners replace the car computer because of the faulty or bad ECM.
In order to pull out your old or faulty ECM, you will need a socket wrench. Using the socket wrench, you need to unbolt the screws that are holding the ECM in the right place. You should be careful about the other components around the ECM place.
Step 5: Insert The New ECM
After unbolting the ECM place screws, the ECM is now not holding in place. So, now you need to insert or replace it with your new ECM. When you buy a new ECM computer from a store, the ECM computer comes up within the box where your ECM will be. Make sure you insert the ECM properly without any difficulty.
Step 6: Bolt The ECM Place Tightly
When the new ECM is in place now, you need to bolt the ECM computer place tightly and currently. Using a socket wrench, you will need to bolt the ECM in place. Better be remember the bolt of the engine control unit computer place should be a tight engine because the vehicle always shakes and vibrates.
Step 7: Connect The Electrical With ECM
As you know, the ECU needs electricity to operate properly. Before you started replacing the vehicle ECM, you disconnected the electricity connection from the Engine Control Module. After inserting the new ECM in the vehicle, you now need to connect the electricity with ECM.
Step 8: Reconnect The Battery Connection
Another thing you should not forget after the replacement of the faulty ECM is to reconnect the battery connection in your car. Using a socket wrench tight the battery cable properly.
You just finished learning how to install ECM properly. When you finish replacing the ECU, you should start your vehicle and allow it to idle for at least five minutes. After five-minute checks for the codes, if there is no defective code appears, that means you successfully replace the ECM.
Things Need To Check Before Replacing ECM
There are some things you need to check before replacing your engine control module (ECM). Most importantly, you need to check the battery charge level and grounding of the vehicle. Checking some of the components before repairing ECM is another important ECM replacement procedure. If you properly check some of the components of your car before replacing the ECM, the ECU replacement will be safe.
Here are things you need to check before replacing your car ECM computer:
- Battery is disconnected
You have to disconnect the battery before you replace the ECM. That’s why check the battery connection in your vehicle and make sure it is disconnected.
- Grounding
Check the ground connections properly. The grounding connection should be tight and in good condition. To check the ground won’t take too long.
- Electrical supply is disconnected
Connections between your ECM and electrical supply need to be disconnected before you replace the ECM in your vehicle.
- Location of the ECM
Finding the engine control unit can be confusing because some vehicles’ ECM is placed in the engine compartment and some vehicle ECM are in the front seats of the vehicle. So, to replace the ECM, the first thing you should know is the location of your ECM.
Mention things you have to check before you start to replace your ECM in the vehicle.
Avoid Unnecessary Return of ECM
Avoid Unnecessary return of ECM means replacing the engine control unit without certainty. Testing your ECM before replacing it is always recommended. As you know, replacing an ECM computer is not cheap; replacing an ECM is very expensive. The average cost of replacing an ECM is around $1000 so it is not that cheap.
Unnecessary return of your engine control module is not a good practice and you have to know this to learn ECM replacement procedure properly. You should be more careful when you want to replace the ECM in your vehicle. Test your vehicle’s ECM properly and find out what the issues are around your ECM.
An engine control module collects data from the different sensors from the vehicle, so there can be any sensor that makes ECM not working properly. Check the sensors and be certain whether your car ECM is bad or any other component that is connected to your ECM.
Using an Onboard Diagnostics scanner (OBD scanner) can help you to find out what the issues are in your ECM. and OBD scanner also helps you to avoid the unnecessary return of ECM. With the help of an OBD scanner, you can read the code and understand the issues and eventually fix those issues.
Why The Engine Control Module Die
The most common reason why your engine control module (ECM) dies or fails is for a burnt circuit board. And when the ECM has a burnt circuit board, it also develops shorts and environmental factors.
There can be other reasons why your ECM goes dead. The corrosion around the ECM board is another reason why the engine control module fails to operate. It is necessary to know if the previous engine control module was burned before replacing it.
A faulty spark plug or coil can make the ECM bad or die. In some cases, the spark plug or coil is the main cause the ECM develops short lies within the shorted solenoid. So, these are the factors or components you need to consider when your ECM goes dead.
Final Thought
You can’t leave a thing around the vehicle engine control module to know the proper ECM replacement procedure. You will know what to do or things to know before replacing the ECM, how to replace the ECM, the unnecessary replacement of ECM, why the ECM goes dead, and more.
Here I tried my best to let you know about the ECU replacement procedure. You will need some knowledge about the engine control unit when you want to replace your ECM. Car computer or engine control unit is a vast subject and important component in a vehicle.
Especially avoiding the unnecessary returning the ECM is not good for your vehicle and also for your pocket. In order to replace the ECM, the reason for ECM replacement should be certain.
Hey there,
How is it going?
I’m Meraj Sarker. I am a Car Mechanic and a student of Automobile Restoration here in Florida, USA. I’ve been studying automotive for around 9 years now. So you can rely on my recommendation. For me, studying and getting knowledge about automobile it’s really fun and entertaining. I will help you to get solutions for your car through this website. If you need any help let me know.
2002 Mitsubishi eclipse GT, got a remanufactured ECM plug and play installed it with battery cables off battery then put cables on battery with a new battery but want start, what did I do wrong?