How to Reset the Engine ECU!

[fabdavrav]

The main correct procedure is as follows!

Turn off all electrical items, stereo, heating to cold, fan speed to "0", etc.

Disconnect battery negative (earth) clamp for 40mins.

FROM THIS POINT ONWARDS DO NOT TOUCH ANY OF THE PEDALS!!!!

Reconnect battery.

Start engine and let idle for 30mins (during this time it will sound as if it will stall, and it will "hunt", this is normal!)

Switch of engine.

Job done!!!

This process wipes the learned values from the ECU and resets to factory defaults. Then it relearns the idle values, and "adjusts" the throttle valve, which it needs to do to operate properly!!! This is a usefull "trick" for most engines, but works very well on VAG cars....got it from the head mechanic at local dealership years ago!

Now you will have to reset the upper limits of the electric windows, and reset the central locking, reset the time on the clock, reset any HIFI settings, security codes etc.!!

To reset the electric windows insert the key into the drivers door lock, and turn the key so that the windows fully wind up and the motors stop, then hold the key in this turned position for a further 4 secs. Job done

Edited 15 September, 2011 by fabdavrav

[musicmaster5000]

This is a work in progress, but the main correct procedure is as follows!

Turn off all electrical items, stereo, heating to cold, fan speed to "0", etc.

Disconnect battery negative (earth) clamp for 40mins.

FROM THIS POINT ONWARDS DO NOT TOUCH ANY OF THE PEDALS!!!!

Reconnect battery.

Start engine and let idle for 30mins (during this time it will sound as if it will stall, and it will "hunt", this is normal!)

Switch of engine.

Job done!!!

This process wipes the learned values from the ECU and resets to factory defaults. Then it relearns the idle values, and "adjusts" the throttle valve, which it needs to do to operate properly!!! This is a usefull "trick" for most engines, but works very well on VAG cars....got it from the head mechanic at local dealership years ago!

Now you will have to reset the upper limits of the electric windows, and reset the central locking, reset the time on the clock, reset any HIFI settings, serurity codes etc.!!

To reset the electric windows insert the key into the drivers door lock, and turn the key so that the windows fully wind up and the motors stop, then hold the key in this turned position for a further 4 secs. Job done

Would this involve having the immobiliser reset or anything?

[fabdavrav]

Would this involve having the immobiliser reset or anything?

No need to reset as it can cope with this procedure...don't worry never had any problems with mine...unless you have an after-market one...when follow the manufacturers instructions.

[musicmaster5000]

Thinking of doing this later on today, I was just wondering what you mean by resetting the central locking?

[fabdavrav]

Thinking of doing this later on today, I was just wondering what you mean by resetting the central locking?

It has to be resynced...details in the owners handbook

[musicmaster5000]

I don't have the owners hand book :/

Okay I do have, ignore that.

Edited 16 July, 2011 by musicmaster5000

[fabdavrav]

I don't have the owners hand book :/

Okay I do have, ignore that.

Found it down the back of the sofa????

I will eventually post up details when I next have my book to hand.

[musicmaster5000]

Found it down the back of the sofa????

I will eventually post up details when I next have my book to hand.

LOL! Nah I wasn't sure what books we had with it. It just says Press any button of the remote control and open the car door with key within 1 minute.

[fabdavrav]

It just says Press any button of the remote control and open the car door with key within 1 minute.

sounds about right from memory!

[musicmaster5000]

Okay, just done it and left the battery disconnected for about 40-45mins and it didn't work :S

[anewman]

I'm not sure disconnecting the battery does run a throttle body adaptation. I'm guessing it can only be done with VAG-COM/VCDS. Also,I believe it relearns values best when you drive normally, as well as idling the car a short time.

To be 100% certain the learned values clear it's probably best to disconnect and leave it overnight.

[Tech1e]

The only way to fully erase learned values is adaptation channel 00 with diagnostics.

If doing a terminal 30 reset (disconnecting the battery) shorting the two terminal clamps together with the battery disconnected with discharge any capacitors and reset systems.

[lee1972]

was thinking of a pipercross induction kitt

and heard best to reset the ecu after fitting so it can adjust

is this true?

i have it remapped will i lose the map

[fabdavrav]

was thinking of a pipercross induction kitt

and heard best to reset the ecu after fitting so it can adjust

is this true?

i have it remapped will i lose the map

You shouldn't loose the map and it might make no differnce as you have a map!....no real harm in trying tho'!

[Ben Cordy]

Not sure if I'm doing something wrong but I'm just sat following your guide now. Upon reconnecting the car has just sat at idle no change in revs at all, hasn't really come close to stalling either as you mentioned it might. It's just sat idling. Trying to get rid of the slight juddering it has at idle. So far it's still juddering!

[Tech1e]

All the OHV engines normally have a slight judder at idle, it's a feature not a fault.

[David 8]

Ross

Does this info apply for all models ??

So in VCDS engine controller> 00 run adaption = reset values ???

[Ben Cordy]

Thanks tech1e although mine is a 1.2 htp, is that still normal?

[Ben Cordy]

I'm inclined to think it hasn't reset to ecu despite leaving it disconnected for 45 mins. The key didn't need resyncing and the windows seemed to just go up and down with the key thing.

[grr666]

RE: post#1

Why aren't the pedals to be touched?

It's obviously very important but for the life of me I can't work

out why?

[fordfan]

They all have an input into the ECU, the clutch switch, the brake light switch and the drive by wire throttle.

[grr666]

They all have an input into the ECU, the clutch switch, the brake light switch and the drive by wire throttle.

Ahh... Cheers, that makes sense

[Tech1e]

Ross

Does this info apply for all models ??

So in VCDS engine controller> 00 run adaption = reset values ???

Normally yes and in most systems

Thanks tech1e although mine is a 1.2 htp, is that still normal?

No, but I was going by your profile.

[Ben Cordy]

No, but I was going by your profile.

Ha sorry haven't updated it yet! So it's not normal?! Fairly sure it didn't actually reset my ecu based on the fact that it didn't do any "hunting" or require me to resync my key etc. I assume the above instructions would be correct for all fabias?!

[john_y]

Ross

Does this info apply for all models ??

So in VCDS engine controller> 00 run adaption = reset values ???

Hi, would this work with 2002 octavia 1.8t 4x4 with me7.x ecu?

Best wishes

John