What Would Cause My ECM To Go Bad And How To Tell

Wondering what would cause my ECM to go bad. Yeah, you should be because the ECU failure causes are important to address as soon as possible.

Symptoms of a bad ECM can also be hard to notice without proper inspection. Whereas an engine control module maintains a vehicle’s performance, it is so obvious that if your car ECM goes bad, it will affect the whole car performance.

Knowing only what would cause my ECM to go bad is not enough because the ECM might need to be replaced; otherwise, a faulty ECM will bring more risky issues into your car.

So, here I will let you know some of the most common ECM failure causes and how to tell if ECM is bad.

What Is A ECM

An ECM is just like a human’s brain. The Engine Control Module (ECM), also known as Engine Control Unit (ECU), is the brain of a vehicle.

An ECM ensures the car’s performance using data. The ECM collects data from various sensors in the car, and using that data; the ECM maintains the whole car’s optimal performance.

An ECM is one of the fundamental components in a car, and that’s why you have to be more careful about it.

What Would Cause My ECM To Go Bad

what would cause my ecm to go bad
What Would Cause My ECM To Go Bad

Corrosion, dead battery, and bad grounding are the common causes of a bad ECM. Corrosion is the most common failure of an ECM because corrosion developed on the ECM board so quickly and brought some serious damage to the engine control module computer.

Some most common cause why car ECM go to bad:

  1. Corrosion
  2. Dead Battery
  3. Bad Jump Starting
  4. Vibration and Thermal Stress
  5. Low Voltage
  6. Bad Starter
  7. Water
  8. Bad Grounding and Loose Wires

1. Corrosion

In most ECM failure cases, corrosion is the main culprit. Corrosion around the ECM is a sign of a bad ECM. Corrosion can be found in the ECM board, wires, and all over the ECU computer. The moisture condition is not applicable to the car’s engine control module.

When moisture goes into the ECM, it transforms into corrosion quickly. All through, the ECM has seals around it for preventing any types of moisture but it won’t prevent it when the ECM goes a number of years. So, corrosion is the first thing to check when you notice your ECM goes bad.

Learn More: Only 6 Steps To Reflash ECU

2. Dead Battery

dead battery

The battery is an essential component to run your vehicle. And the battery has a direct connection with the car ECM computer.

Car batteries need to be functioning properly to operate the engine control module. The car battery develops dead cells that eventually make your car battery dead.

So, when your car battery is dead, it won’t be able to supply the power to the ECU computer, and eventually, your car ECM also can’t be operated.

The best practice is when you notice your ECM is failing to check the battery properly. Look for any issues with the battery that prevent providing power to the ECM. With a dead battery, your car can’t move or run.

3. Bad Jump Starting

bad jump starting

When we jump-start the car, that means the external supply of electricity recharges the dead or disabled car’s battery and the jump start also provides some of the power that helps that car crank the engine.

But if you do jump starting in an incorrect way, it can short out the ECM. Bad jump-starting happens for incorrectly attaching jumper cable, or jumper cable is not in good condition and other reasons.

So, you should try your best to avoid the bad jump starting in your car. Avoiding bad jump-starting is good for your car and also for your car’s ECU computer.

Your car ECM might need to be replaced for the bad jump start.

4. Vibration and Thermal Stress

Your ECM can go bad for vibration and thermal stress. There is no chance to consider vibration and thermal stress to be minor issues in your car.

The vibration and thermal stress can creak to form in the engine control module’s circuit boards. If the ECM’s circuit board creaks, there is no way to repair the ECM; you have to replace it as soon as possible. That’s why you should be more aware of your car’s vibration and thermal stress.

5. Low Voltage

low voltage

To control the whole car’s components and maintain the engine’s optimal performance, the ECM needs a sufficient amount of voltage.

A properly functioning ECM needs 12 volts, not less than 9 volts, to operate. In the harness of ECM, you will find writing that supplies the voltage.

Check the voltage using a voltmeter gauge and see how much voltage is running through the ECM.

If the voltmeter gauge displays less than 9 volts, then your ECM failure for the low voltage. After detecting the low voltage issues in the car, you should not leave as it is because it can bring more issues in the ECM and the car.

Read More: 4 Steps To Test ECU With Multimeter

6. Bad Starter

bad starter

The starter motor turns over or cranks the engine to start, so that means a starter motor is an essential component in a vehicle.

A starter motor is an electrical motor that helps a car to start. And the ECM collects data and gets the voltage from this starter motor to control that car.

Obviously, if the starter motor is not good or it’s been bad, the starter motor won’t be able to give the right data and right amount of voltage to the ECM, which will eventually be a cause of ECM failure.

Sometimes car owners purchase an unmatched starter motor that is not combined with the ECM. You have to make sure when you buy a starter motor sensor for your car; you have to buy the right starter sensor that is matched with the engine control module.

7. Water

Water can damage car's ECM
Water can damage car’s ECM

If you want to make your car live longer, then water is the first thing you must avoid getting in your car.

Water can remarkably damage some of the components in a vehicle, and the ECM is one of them. If the small amount of water can manage to go into the engine control unit, it will make your ECU shorted out.

Another thing you need to be aware of is corrosion if the water goes to the ECM because water will develop corrosion in your ECM circuit board, which will lead your car ECM to go bad.

Learn More: ECM Repair

8. Bad Grounding and Loose Wires

Bad grounding and loose wires connection will bring faulty inputs and problem codes to your ECM. When you have an ECM failure issue in your vehicle, you have to look for the bad grounding and loose wires contention in your vehicle.

Your ECM can blow-ups and short circuits if bad grounding and loose wires are in your ECM’s harness. That’s why if you want to know what causes your ECM to go bad, then checking bad grounding and loose wires is an essential task to complete.

How To Tell If ECM Is Bad

Knowing only what causes your ECM to go bad is not enough because you need to be certain that your car ECM is bad before replacing it or taking any steps.

There are some bad ECM symptoms that you can consider. The most common symptoms of a bad ECM are “Check Engine” light is on, and the car failed to start. There are also various signs of a bad ECM you need to know.

Here are some common symptoms of bad ECM :

  • The engine is stalling
    Your car stalls frequently, which is a sign of bad ECM. in some bad ECM cases, you will see your engine stalls or misfires not so often, but you also need to check that as soon as possible.
  • Check engine light is on
    Knowing the ECM is bad or not is very easy when you see the check engine light. If your car’s check engine light is on, that indicates your car ECM is having an issue or ECM is failing.
  • The engine won’t start
    One thing you will experience if your car ECM is bad is that you won’t be able to start the engine. You can also experience that your car will crank but not start if the ECU is bad.

Make sure you look for bad ECM symptoms in your car because when you know what causes an ECM to go bad, you should also know what the symptoms of a bad ECM are. These are the symptoms you will experience when your car ECU goes bad.

Final Thoughts

No matter which of the vehicles you drive, your vehicle has an ECM computer. And knowing what would cause my ECM to go bad is a necessity.

There are some common reasons why your car ECM goes bad and eventually costs you a lot of money. Taking instant and proper action can save your expensive engine control unit (ECU).

Remember, the ECM circuit board is the main part of an engine control module computer because you won’t be able to repair the ECM circuit board.

If something happens to your ECM circuit board, you have to replace that. That’s why avoiding water from the ECM computer is good practice.

After finding ECM failure causes and getting the symptoms of a bad ECM, you need to be more certain about these issues in your vehicle.

If you don’t have lots of experience regarding the engine control module, you should get a mechanic consultant to address the bad ECM causes.

Now, if you need to check all of these possible causes in your car and be certain what is the main cause your car ECM goes bad.

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2 thoughts on “What Would Cause My ECM To Go Bad And How To Tell”

  1. 02 s10 4.3 2 wldr 189,00 kwas run fine little low on oil but run fine had a snooze when to start it and it ran worst than dog shit tastes sounded like i was missing on a couple of cyilners so i thought get a code be dasmmed if i can find it not under steering wheel or fire wall or behind glover box had ither people look nope no go and my dash is down unrelated for awhile no so could finf egr vale either i fell…challengded on a mental level lol.so what was put in my tank to make it go south right off the start and how do i procced dont want to lose another to vandells er what ever

    • Hello Mr Jan Svekla,
      How is it going?
      Thank you for your comment. We appreciate it a lot.

      Mr Jan Svekla, would you please tell me what is actually wrong in your vehicle. More specific question would be great to us for determine what is the problem is and what you need to do.

      Thank you for your contribution to our caralso.
      Have a good day, Mr Jan Svekla


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