ECU Reset (Without Disconnecting Battery)
#1
ECU Reset (Without Disconnecting Battery)
Here is how to reset your ECU without disconnecting your battery. This is a solution for those who install new parts and do not want to risk losing their trip meter mileages, radio presents, and so on.
Some people have told me this does not work on the tC. Whether or not they did it right is beyond me. This has worked with other cars... If someone can get back to me on this, that would be very helpful.
Update:
- Make sure the car is off and that the key is not in the ignition.
- Open the hood and locate the "Engine Room Relay Box." This is the fuse/relay box in the engine bay. On the xA/xB, it is the black top box to the right of the engine bay.
- Take the black cover off and flip it over to read the embossed diagram. You want to look for the EFI fuse (not RELAY). On the xA/xB, the EFI fuse is 15 Amps. On the tC, the EFI fuse is 20 Amps.
On the xA, the EFI fuse is #4:
On the xB, the EFI fuse is #12:
- Using the fuse-puller (white piece of plastic in the box), pull the EFI fuse out and let it sit for 10-30 seconds.
- Pop the fuse back in the EFI fuse socket. Make sure it is properly seated and is uniform with the other fuses.
- Put the black cover back on.
- Cross your fingers, start up the car, and hope you don't pull another CEL (Check Engine Light).
- If you are successful in not pulling a CEL, I recommend you let the car for 5-10 minutes for good measure.
Some people have told me this does not work on the tC. Whether or not they did it right is beyond me. This has worked with other cars... If someone can get back to me on this, that would be very helpful.
Update:
Originally Posted by toastbox
Mikochu, in the unlikely event that you are still monitoring this post, this fix 100% works for the tc. I used it this weekend when installing a SRI. Thanks!
#5
Originally Posted by shinkuu
wouldn't it be faster and easier to disconnect the battery since you're under the hood anyways?
Originally Posted by mikochu
This is a solution for those who install new parts and do not want to risk losing their trip meter mileages, radio presents, and so on.
#7
i did it that way when i installed did the poor mans intake mod, i unplugged the maf and then did the fuse thing and it felt as if i lost power ...so i redid it but just unplugged the maf without doing the fuse thing and it pulls much better..... i thought it might have been that i didn't wait enough so i did it a few times and it was that. strange but i am against pulling out your efi fuse from experience!
#8
I read on Consumer Reports:
Obtain a fresh unused 9V battery (those rectangular shape battery). Obtain a 9-Volt Vehicle DC-to-DC Adapter (one end plugs in your cig. lighter; the other end has connection for a 9V battery. Plug the 9V to the adapter> Plug the adapter to the cig lighter. It should work, according to CR.
Obtain a fresh unused 9V battery (those rectangular shape battery). Obtain a 9-Volt Vehicle DC-to-DC Adapter (one end plugs in your cig. lighter; the other end has connection for a 9V battery. Plug the 9V to the adapter> Plug the adapter to the cig lighter. It should work, according to CR.
#10
Originally Posted by scixB
so if i isntaled an cold air intake and a new exhuast system..then i need to do this right?
i feel that my rpms and motor is running funny.
i feel that my rpms and motor is running funny.
#15
Originally Posted by asirvr4
nice idea
i understood everything and i am fine
but, what you meant by "those who install new parts"?
what parts? like what??
i understood everything and i am fine
but, what you meant by "those who install new parts"?
what parts? like what??
#16
^^^ does that include things like carbon fiber door sill plates? I
Mikochu, in the unlikely event that you are still monitoring this post, this fix 100% works for the tc. I used it this weekend when installing a SRI. Thanks!
Mikochu, in the unlikely event that you are still monitoring this post, this fix 100% works for the tc. I used it this weekend when installing a SRI. Thanks!
#18
Originally Posted by Tito_Cruz
Is there anyway to be sure the ECU reset after doing this?
#19
Originally Posted by toastbox
Originally Posted by Tito_Cruz
Is there anyway to be sure the ECU reset after doing this?
#20
Originally Posted by Tito_Cruz
Oh, thanks! Although, I was actually looking for some kind of "landmark" that I could look for after reseting it to assure me that I did it right. I'm installing a CAI so I'm guessing a power gain would be something to lookout for. I'm guessing that If the engine doesn't run well anymore or my gas mileage dramatically drops...I can tell the ecu didn't reset....???
Just remember to let the car idle for 5-10 minutes before you drive it. Regarding Gas mileage....most likely your first two tanks are gonna be significantly lower...I say that because when you hear how aggressive the new intake is, you're gonna jamming the gas all the time, and winding it up. I typically averaged about 23-24 or so in town, prior to the intake. MY first two tanks after wards were 20.x But that's because I was shifting at 4-5000 rpm's, not 2800. Once I got over the noise/aggressiveness, the gas mileage went back up to 23 ish.