Last updated on April 3rd, 2022 at 11:34 am
Engine problems or simply electrical problems can be annoying. Engine control module related problems might end up being really costly. But sometimes the problems with your vehicle or basic electrical systems are originating in a faulty engine control module, and you’ll only have to do a simple reset to get your engine firing properly again (Assuming that is all it needs. )
Can A ECU Be Reset? Yes! The ECU can be reset, and you should try to do this in situations where the engine is experiencing problems that are originating from the ECU. While it can be hard to tell when you have an ECU that is experiencing problems.
What Are The Symptoms Of A Bad Powertrain Control Module? You may not even need to have scan tools to see a bad engine control unit. If the check engine light is flashing or the engine has problems, you might have a bad powertrain control module. At this point, scan tools can be used to see the exact problem that you might be having with the ECU.
How Do You Reset Your Car's Computer? Resetting your car’s engine control or control model requires that you reset the computer on your car. First, open up the hood. You’ll want to do this in daylight or in a well-lit area. You’ll next need to remove the positive cable from the car battery. Use pliers to do this. Find the fuse box in the car and find the fuse that should be labeled ECM. The ECM is the electrical control module. Disconnect this fuse for a few minutes, and the memory on the computer should clear.
Will Disconnecting Battery Reset ECU? Just unplugging the battery may not be enough to reset the ECM in many cars because there is backup power and a fuse box which prevents the engine control module from being wiped in natural conditions. You don’t want to lose all your data every time you put a new battery in the car.
No, your car will not reset the ECU and relearn procedures everytime a battery is disconnected or replaced. If that were to occur then the ECU would reset every time your car was replaced. Like we talked about in the section above, you’ll need to disconnect the battery and detach the ECU fuse for a few minutes to get a reset.
What Happens When You Reset the ECU? The ECU is the learning module of the car. Depending on the age of your car, it does a lot of different things, like control the firing of the engine and help you maximize fuel economy. If it is functioning well, the electrical control unit helps you drive and extends the life and gas mileage of your vehicle. If the ECU starts to malfunction, you can lose control of the idle speed and have bad sparks and problems starting. Your ECU also stores any malfunction codes which can help you and mechanics diagnose what is wrong with the vehicle. 
Is it Bad to Reset an ECM? Nope, it’s not bad, but it can cost you a little bit in the efficiency and maintenance of the car. Resetting the ECM can wipe some of the learning that the car has done about how it drives and how you drive it. This can cost you a bit in fuel economy as the car picks up again, but it isn’t anything to worry about.
Difference Between an ECU and ECM There is no difference between an ECU and ECM, just different names for the same part on different kinds of cars. The two acronyms and the phrases--electrical control unit and electrical control module--are used interchangeably.
What if My ECU is Broken? If the check engine light has come on in the computer, you might want to take a code reader and get the trouble code. You can google error codes to see if the car computer or powertrain control modules might be broken. Of course, one of the problems with diagnosing a bad ECU is that the ECU is responsible for finding and sending error codes to the reader. If the ECMS fuses or the ECM itself is not working properly, you might not get the right diagnosis.
ECMs can be annoying to replace, and you might pay just under a thousand dollars for it.
Engine Control Module Soft Reset
A soft reset on the ECM is possible, but is more difficult to do. You can jump battery cables for 30 minutes or you can put a resistor into the electrical series and power down the vehicle. Either way, soft PCM resets are a lot more difficult and complicated to do. Unless you are a pretty experienced mechanic, you should leave it to the pros.
If someone replaced an ECM with a used ECM, would it have the old vin number and the old mileage on it ? In other words, could you reprogram a used ECM with the new car’s vin and leave the old car’s mileage on it.