Engine ECU Reset. Anyone know how?

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Dibber
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Engine ECU Reset. Anyone know how?

Post by Dibber » 15 May 2019, 22:53

I want to clear the adaptions on my engine ECU on my C2.
I have read a few posts elsewhere on ways to do it but the information seems dubious. Some are nothing more than battery disconnects. Others are effectively BSI resets.

Is it the case there is no method other than Lexia or one of the pro level scanners?

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Paul-R
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Re: Engine ECU Reset. Anymore know how?

Post by Paul-R » 15 May 2019, 22:57

You'll have to explain a bit more what you mean by adaptions. I don't know that word.

What is the problem that you think might be fixed clearing an "adaption"?

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GiveMeABreak
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Re: Engine ECU Reset. Anyone know how?

Post by GiveMeABreak » 15 May 2019, 23:19

Dibber wrote:
15 May 2019, 22:53
I want to clear the adaptions on my engine ECU on my C2.
I have read a few posts elsewhere on ways to do it but the information seems dubious. Some are nothing more than battery disconnects. Others are effectively BSI resets.

Is it the case there is no method other than Lexia or one of the pro level scanners?
There are no adaptations you can change. The engine ECU constantly makes adjustments as necessary dependent upon conditions to ensure optimum operation. Things like outside temperature, air pressure for example. The ECU is pre-programmed at factory to meet the desired requirements and Euro standards.

A BSI reset done properly will only reinitialise ECUs, it will not change the software programme.

The only other sort of adaptations are for equipment like an Auto gearbox, Piloted Gearbox for example.

doctle
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Re: Engine ECU Reset. Anyone know how?

Post by doctle » 16 May 2019, 00:08

If the ECU has been remapped you can get it returned to factory settings. The remapper usually keeps the original file

Dibber
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Re: Engine ECU Reset. Anyone know how?

Post by Dibber » 16 May 2019, 06:53

Adaptions are alterations to the base map the ECU learns over time through drive cycles which then get stored in it.
An instance of that would be long term fuel trim. When shutting off the engine, specifically in my own car, the ECU remains alive for a short period of time to allow it to store in the ECU any changes to the adaptions it has learnt through its last drive cycle. The next time the engine is run it then uses that stored data.

Dealer level software or higher end scan tools have the ability to reset adaptions. This can be used to reset adaptions to the original base setting then usually you need to drive the car in various drive cycles for the adaptions to relearn.

On my particular car there will be very few adaptions but on more complex engines there would be stored adaptions for the likes of variable valve timing.

My friend that used to work at PSA said when they were diagnosing certain types of faults the first thing they would do is clear the adaptions as often PSA would recommend that this was tried. Also, when fitting specific new components to engines PSA would recommend resetting adaptions.

Adaptions can get stuck or corrupted in the ECU and need to be rebooted. In my case I want to reset my fuel trim adaptions as my long term fuel trim has got stuck.

On my other car I had an issue with dirty solenoids that control the oil flow to the system that controls the cam timing. In the dealer level software I was able to run a purge of those solenoids to try and clean them. As it turns out, I had to actually remove and manually clean them, then reset the adaptions specific to those components.

I remember on that particular car there was a section in the dealer software for adaptions and you had an option to clear all adaptions or pick out individual ones to reset.

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GiveMeABreak
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Re: Engine ECU Reset. Anyone know how?

Post by GiveMeABreak » 16 May 2019, 12:35

There is nothing you can do to change parameters using Diagbox. An engine 'Tuner' will interface with the ECU using specialist equipment - and that is beyond the purview of this forum. Some ECUs are locked and some have to be taken off and put on a bench. The only thing you can do with the Engine ECU with Diagbox is the configuration of the type of gearbox, A/C, battery, alternator etc. etc. that is fitted to the vehicle and that is only required so the configuration has become corrupt. Normally this is downloaded directly from PSA servers at the dealer - and if this was ever required, it is likely that any ECU software udpate will overwrite any stored parameters - negating any 'tuning' done by a third party.

The parameters Dibber is referring to apply to most ECUs on the vehicle. They store recent journey parameters and are used for determining driving conditions, fuelling information, regeneration (on diesels), type of road (hydractive suspension vehicles), turbo info, battery condition, stop start info on capacitors etc etc.

A proper BSI reset will just ensure that networked ECUs are allowed to go into sleep mode and are later awakened again to ensure they are in the correct 'state'.

I think if you have a specific issue you should be looking at a proper diagnostic and taking it from there.

wheeler
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Re: Engine ECU Reset. Anyone know how?

Post by wheeler » 16 May 2019, 13:51

I think he is referring to the auto adaptives? where the ECU learns driving styles etc?
If so then you can do this with Lexia (depending on the ECU fitted), It is under the sub menu- initialise auto adaptives. It resets the ECU back to base settings & does not need access to the PSA servers.
It should be done when replacing certain components like oxygen sensors & electronic throttle bodies etc, Lexia advises when you go into the menu.
The procedure varies slightly depending on which ECU is fitted. Some it is literary just a click of the button, some require a road test.

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GiveMeABreak
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Re: Engine ECU Reset. Anyone know how?

Post by GiveMeABreak » 16 May 2019, 14:00

That's what I suspected - like I mentioned in my last post like the Auto adaptives / actuators etc.

I would just add a word of caution though - it has been known that some clones can corrupt some ECUs - an example being the Parking Assistance ECU - there is an issue with some clones that leaves the ECU incorrectly configured and affects the system, so as long as you are aware. I've also had this happen with the EPB ECU / BSI concerning some functions where the programming was incomplete and took 6 or 7 attempts before a software update was needed to get it configured correctly.

Clones are really useful but not infallible. :wink:

Dibber
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Re: Engine ECU Reset. Anyone know how?

Post by Dibber » 17 May 2019, 07:17

Thanks guys. Wheeler that info you posted is very helpful for me.

Marc I still have not pulled the trigger on a Lexia clone as yet. I think you mentioned to me before that some of them can be a bit iffy.

I had wondered if there was an alternative method without the use of advanced diagnostic equipment but that's looking more and more like wishful thinking on my part

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GiveMeABreak
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Re: Engine ECU Reset. Anyone know how?

Post by GiveMeABreak » 17 May 2019, 10:43

Unfortunately, tweaking settings with a screwdriver and a spanner are long over! :-D