How to Reset the ECU on a Jeep Wrangler JK

[Chris]

While there are folks that swear resetting your ECU does absolutely nothing, it's a common practice among automotive enthusiasts. The ECU (Electronic Control Module) "learns" your driving style and the parts in your ride by storing information in its memory, information that it gathers using a number of sensors located all throughout the vehicle. After installing new or performance parts, you can reset the memory in the ECU and force it to "relearn" the vehicle's modifications and your driving style with just a few simple steps, which will allow you to take full advantage of the accessories you have added. Keep reading and we'll walk you through the process for resetting the ECU.

Material Needed

• Adjustable wrench

Step 1 – Ground the battery cables
Pop the hood and disconnect the positive battery cable from your battery. Ground the positive battery cable to the negative battery cable for 30 seconds. This will erase the electronic charge in the capacitors, which is what retains the ECU's memory. After 30 seconds has passed, reconnect the positive battery cable and shut the hood.

Figure 1. Remove the positive battery cable and ground it to the negative cable for 30 seconds.

Step 2 – Manipulate key and headlights
Insert the key in the ignition, but don't start the vehicle. Turn the key to the "ON" position, then turn the headlights on and back off. Turn the key off. The ECU will be reset to factory settings at this point. Over the next 50 warm-up periods, the ECU will gather the necessary information involving your driving habits and the parts installed on the vehicle.

Figure 2. Turn the key to the "ON" position.

Figure 3. Turn the headlights on then off, and remove the key.

 

[nomo$inpocket]

Thanks, i'll try that tomorrow, can't hurt.

 

[BLACKJKU]

Sometimes the easiest fixes are the free ones.

 

[Bradleysmall79]

While there are folks that swear resetting your ECU does absolutely nothing, it's a common practice among automotive enthusiasts. The ECU (Electronic Control Module) "learns" your driving style and the parts in your ride by storing information in its memory, information that it gathers using a number of sensors located all throughout the vehicle. After installing new or performance parts, you can reset the memory in the ECU and force it to "relearn" the vehicle's modifications and your driving style with just a few simple steps, which will allow you to take full advantage of the accessories you have added. Keep reading and we'll walk you through the process for resetting the ECU.

View attachment 112634

Material Needed

• Adjustable wrench

Step 1 – Ground the battery cables
Pop the hood and disconnect the positive battery cable from your battery. Ground the positive battery cable to the negative battery cable for 30 seconds. This will erase the electronic charge in the capacitors, which is what retains the ECU's memory. After 30 seconds has passed, reconnect the positive battery cable and shut the hood.

View attachment 112635
Figure 1. Remove the positive battery cable and ground it to the negative cable for 30 seconds.

Step 2 – Manipulate key and headlights
Insert the key in the ignition, but don't start the vehicle. Turn the key to the "ON" position, then turn the headlights on and back off. Turn the key off. The ECU will be reset to factory settings at this point. Over the next 50 warm-up periods, the ECU will gather the necessary information involving your driving habits and the parts installed on the vehicle.

View attachment 112636
Figure 2. Turn the key to the "ON" position.

View attachment 112637
Figure 3. Turn the headlights on then off, and remove the key.

Sweet I'll give it a try and pray she works. Thank you

 

[Chris]

Sweet I'll give it a try and pray she works. Thank you

You're welcome!

 

[Bradleysmall79]

You're welcome!

Ok so I did the reset and it drove great. Parked it drove it again and the codes came on again and right back to the rough idle. Idk what to do next

 

[BLACKJKU]

I had to do this when I put the Viper Throttle Body on my JK to reset it. Go about 1/2 way down the page to where it says Chrysler 300 electronic throttle control light reset. See if that helps, if not you could have gotten a bad TB.

 

[BLACKJKU]

I had to Do it 2 times and the 2nd time I did it I went slower with the pedal then the first time. Are you getting the lightening bolt and then limp mode? If so all you have to do is turn the key off then back on and it will reset then be good and you can go on with your plans.

It was after the 2nd reset that it finally fixed it and that was about 1.5 years ago.

 

[Bradleysmall79]

I had to Do it 2 times and the 2nd time I did it I went slower with the pedal then the first time. Are you getting the lightening bolt and then limp mode? If so all you have to do is turn the key off then back on and it will reset then be good and you can go on with your plans.

It was after the 2nd reset that it finally fixed it and that was about 1.5 years ago.

Ok thanks bro, I'll give another try and pray she likes it this time haha

 

[GVENT]

Sorry to jump in so late, but would this be what you'd do if you replaced your fuel injectors?

 

[BLACKJKU]

Sorry to jump in so late, but would this be what you'd do if you replaced your fuel injectors?

Usually need to do a reset if you replace a part because your CEL is on, and after replacing the part the CEL doesn't go away.

 

[GVENT]

While there are folks that swear resetting your ECU does absolutely nothing, it's a common practice among automotive enthusiasts. The ECU (Electronic Control Module) "learns" your driving style and the parts in your ride by storing information in its memory, information that it gathers using a number of sensors located all throughout the vehicle. After installing new or performance parts, you can reset the memory in the ECU and force it to "relearn" the vehicle's modifications and your driving style with just a few simple steps, which will allow you to take full advantage of the accessories you have added. Keep reading and we'll walk you through the process for resetting the ECU.

View attachment 112634

Material Needed

• Adjustable wrench

Step 1 – Ground the battery cables
Pop the hood and disconnect the positive battery cable from your battery. Ground the positive battery cable to the negative battery cable for 30 seconds. This will erase the electronic charge in the capacitors, which is what retains the ECU's memory. After 30 seconds has passed, reconnect the positive battery cable and shut the hood.

View attachment 112635
Figure 1. Remove the positive battery cable and ground it to the negative cable for 30 seconds.

Step 2 – Manipulate key and headlights
Insert the key in the ignition, but don't start the vehicle. Turn the key to the "ON" position, then turn the headlights on and back off. Turn the key off. The ECU will be reset to factory settings at this point. Over the next 50 warm-up periods, the ECU will gather the necessary information involving your driving habits and the parts installed on the vehicle.

View attachment 112636
Figure 2. Turn the key to the "ON" position.

View attachment 112637
Figure 3. Turn the headlights on then off, and remove the key.

Sorry to jump in so late, but is this something you'd do if you replaced your fuel injectors?

 

[Chris]

Sorry to jump in so late, but is this something you'd do if you replaced your fuel injectors?

Nope, I wouldn't worry about it in that case.

 

[Clint]

Ok so I did the reset and it drove great. Parked it drove it again and the codes came on again and right back to the rough idle. Idk what to do next

Change your fuel filters maybe?

 

[Chris1227]

This may sound dumb but what do you mean by ground the positive to the negative? Take the positive cable and put it on top of the negative cable?

 

[spiderbobr]

So you are saying to remove the "Positive" cable and hold it to the negative cable for 30 seconds.
Is it necessary to have the ground (negative) cable still attached to the terminal of the battery? I ask as this, as this could pose a dangerous move for some people not familiar with batteries, as rule of thumb is to always remove the negative cable first on a battery to reduce the chance of spark and ignition of battery gases.

 

[BLACKJKU]

Remove BOTH cables from the battery and then touch them together.

 

[spiderbobr]

That is exactly what I told my son, but he needed someone else to say that. Good side, he feels better now.

 

[Olikara]

While there are folks that swear resetting your ECU does absolutely nothing, it's a common practice among automotive enthusiasts. The ECU (Electronic Control Module) "learns" your driving style and the parts in your ride by storing information in its memory, information that it gathers using a number of sensors located all throughout the vehicle. After installing new or performance parts, you can reset the memory in the ECU and force it to "relearn" the vehicle's modifications and your driving style with just a few simple steps, which will allow you to take full advantage of the accessories you have added. Keep reading and we'll walk you through the process for resetting the ECU.

View attachment 112634

Material Needed

• Adjustable wrench

Step 1 – Ground the battery cables
Pop the hood and disconnect the positive battery cable from your battery. Ground the positive battery cable to the negative battery cable for 30 seconds. This will erase the electronic charge in the capacitors, which is what retains the ECU's memory. After 30 seconds has passed, reconnect the positive battery cable and shut the hood.

View attachment 112635
Figure 1. Remove the positive battery cable and ground it to the negative cable for 30 seconds.

Step 2 – Manipulate key and headlights
Insert the key in the ignition, but don't start the vehicle. Turn the key to the "ON" position, then turn the headlights on and back off. Turn the key off. The ECU will be reset to factory settings at this point. Over the next 50 warm-up periods, the ECU will gather the necessary information involving your driving habits and the parts installed on the vehicle.

View attachment 112636
Figure 2. Turn the key to the "ON" position.

View attachment 112637
Figure 3. Turn the headlights on then off, and remove the key.

Chris....I was stressed out when my JK started in the morning and the wipers kept going up and down, gears wouldn't move....saw your post....took me about 10mins and everything got back to normal. Thank you so much for sharing...Great help

 

[Chris]

Chris....I was stressed out when my JK started in the morning and the wipers kept going up and down, gears wouldn't move....saw your post....took me about 10mins and everything got back to normal. Thank you so much for sharing...Great help

So glad to hear that! You're welcome