How To Reset Car ECU Without Disconnecting Battery

If you’re a car owner, then you’ve faced car computer default at least once in your life. That’s because they’ve prone to malfunctions. You may find “check engine” lights on or wrong information on the dashboard. Whatever it may be solved by resetting your Car Computer or ECU. A faulty car ECU may have a huge negative impression on a car’s performance. 

But you can solve this little problem by resetting the car’s ECU or ECM. It’s not that hard to do what you think. With proper knowledge and tools, you can reset the car’s ECU without disconnecting the battery. Read till the end to know the symptoms of a faulty car ECU and get proper knowledge on resetting the car ECU without disconnecting the car battery.  

What is ECU or ECM?

A car’s computer is known as ECU or ECM. ECU refers to the Engine Control Units, and in the same way, ECM goes for Engine Control Modules. Both ECU and ECM are the same, just representing the car’s computer in different ways. In the car, ECU is compared to a brain that operates the whole function properly. 

Ignition, alternator, power supply and energy regulation, sound, radio and driving subsidiary on the dashboard and the overall exterior and interior electrical features are all connected with the car computer. If any of them fail to work correctly, the overall module goes wrong. ECU is programmed to operate normal functions in the car and memories driving patterns. If anything goes wrong, you get dreadful signals.

ECU Failing Symptoms

When you’ve ECU difficulties, it has several symptoms. These symptoms may come out indicating some specific problem but ultimately ends up with ECU issues. Five significant signs of ECU failure. 

  1. The “Check engine” light is on all the time.
  2. Starting issues remain all the time though all are Okay.
  3. Car performance gets low after proper maintenance. 
  4. Wrong information on the dashboard. 
  5. Burning smells come out when some short circuit happens, which can lead to ECU failure at the end.

Though each of these signs indicates a particular issue, it may result in a car computer resetting. Besides, it has some benefits of resetting the car computer.

ECU reset Benefit

Engine control modules get overloaded by getting information on driving patterns. Overloaded ECUs are prone to fail frequently. So it would be best if you had a periodical quarry when it’s close to being overloaded. Resetting the car’s computer lets you free some space and remove some unnecessary information. 

Resetting the car’s  ECU is safe; it’ll not break down in the system. It’ll just erase some particular information in your car’s computer, not the entire memory.

Step By step procedure to reset car ECU

You can reset your car in two ways. One is resetting the car computer without disconnecting the car battery, and the other is resetting the car computer by disconnecting the car battery. Both are quite easy. You don’t need to disconnect the car battery to reset your car. Here is a step-by-step guide to resetting the car ECU without disconnecting the car battery.

  1. First of all, drive your car for at least 15 minutes to warm up the engine and start the car’s computer. It ensures normal operation in the car ECU.
  2.  After warming up, turn off your car and remove the ignition key and take your car to a safe place where you can reset the ECU.
  3.  Then it would help if you found the interior fuse panel. Take help car’s manuals to find it out. Usually, it’s under the footrest.
  4. Remove the fuse box and find a fuse labelled ‘Back-up’ and ‘ECU or ECM’. Remove both fuses. 
  5. You need to remove the fuses for 15-20 minutes. After that time, reinstall the fuse again.
  6. Then lock the fuse box carefully and leave it as before.
  7. You are almost done. You’ve reset the fuse successfully. Now drive your car for minutes. It will help your car’s computer reassemble your car’s driving pattern instantly and will adjust the programmed operation.

Safety Tips

Resetting a car’s computer is not that hard, but you need proper knowledge and tools. Always use the car’s manual for any quarry. To reset the car ECU, disconnecting the battery is not necessary. But if it becomes a necessity, then maintain the procedure to disconnect the battery or take help from professionals.

Final Words

Resetting a car ECU with a battery is a simple task with proper knowledge and tools. There is a particular fuse for ECU to remove and reinstall to reset car battery sensors. Here we mentioned a step-by-step guide to resetting your car’s Engine Control Unit. No matter how limited your knowledge about a car’s function is, this guide can properly let you reset the car’s ECU or ECM. I hope you can fix your car’s  ECU problem.   

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