Question: Will Removing The Negative Battery Cable Reset Computer?

What happens if you unplug the ECU?

However, if the ECU is unplugged, it will retain any charge it may have even if you create a power draw someplace else in the vehicle.

So you’d need to wait a decent amount of time to be “sure” it’s drained.

Some folks go so far as to unplug the battery and let the car sit over night..

How long do I have to drive my car to reset the computer?

So why is the light still on? Here’s something you probably don’t know: after clearing the car’s computer you will need to drive for about 50 to 100 miles. As you drive your car the computer will monitor all the sensors and register the results.

What happens when you disconnect the negative battery cable?

If you remove the negative clamp and inadvertently complete a circuit to ground, there will be no current flow because the ground clamp is already grounded. Subsequent shorting of the positive terminal to ground will then produce no current flow because the current has no return path to the negative post.

Why you should remove the positive terminal after removing the negative?

Usually removing the positive cable first will cause no problems. However, removing the negative cable first is safer because it eliminates the possibility of having a short circuit if you inadvertently touch a tool to both the positive terminal and a metal part of the car at the same time.

Should Battery Disconnect be on positive or negative?

The negative cable connects to the body ground already—so there’s no additional danger if it rubs. It’s the same principle as why you should always disconnect the battery’s negative side first before performing electrical service.

Which battery terminal Do I disconnect for storage?

The low-tech solution is to disconnect the negative battery cable. You’ll likely lose the stereo presets, time and other settings. If you want to keep those settings and ensure that your battery starts the moment you return, purchase a battery tender, also known as a trickle charger.

Which battery cable do you remove to reset the computer?

How to Reset a Car ComputerOpen up the hood.Remove the positive terminal cable from the battery using your pliers or wrench.Go to your fuse box in your car, and look at the diagram. … Keep the car disconnected like this for two to three minutes to clear the computer’s memory.

Should I disconnect both battery terminals?

No, it won’t. You can disconnect whichever terminal you want, or even both, it won’t discharge. Whichever one you choose results in an open circuit so no current can possibly flow.

Do you take negative positive off first?

Always remove the negative cable first. … Detach the black/negative (-) cable from the battery. Detach the red/positive (+) cable from the battery.

How long do I leave battery disconnected to reset ECU?

It’s a real tight fit, but if you can find it and disconnect it, leave it disconnected for 30 seconds. The nice thing about this method over the “disconnect the negative cable” method is that you don’t have to reprogram your radio! If you can’t find it, then do the negative cable – again for about 30 seconds.

What happens if you connect the negative terminal first?

The negative cable is connected to the body/chassis of the car. … If you connect the negative first, then the positive, if you happen to touch the wrench to something metal while it is touching the positive terminal, that’s a short – because the chassis is already connected to the negative battery terminal.

How do I reset my ECU without disconnecting the battery?

Easy Way to Reset ECU without battery disconnect With the key in your pocket/car, push the Engine Start button TWICE (so the car is fully on, but not started) Within three seconds of the car “ON” (again NOT started), Floor (all the way down) and Release the gas pedal fully 5 times within 5 seconds.More items…•

Do I disconnect the positive or negative to reset ECU?

When removing cables, remove negative first, then positive. If you just want to reset the ECU, removing only negative is good enough. When installing cables, install positive first, then negative.

Does disconnecting battery reset ECU?

Will disconnecting battery reset ECU? Can a ECU be reset? Yes, all ECU (Engine Control units) can be reset and be should reset once per manufacturer’s guideline for a smooth relearn process or upon installing a replacement unit.

Why do you remove the negative battery cable first?

By removing the negative battery cable you are disconnecting the battery from the chassis of your vehicle. If you begin to remove the positive side before the negative and your wrench would make contact with any part of the vehicle, then you could cause a short in the system.