Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

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jamescarruthers
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Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by jamescarruthers »

Hello everyone,

My sister’s car is in at Chevronics and they say it needs a new Eolys FAP additive ECU.

This is the one from the car
57863047-4409-49F3-9763-F2C211FDE8D4.jpeg
It is possible to find other ones with the EAS100.01 number on but not with 09733009902 on it which I will presume is important unless someone can tell me otherwise!

Any ideas on where I might find a replacement. Do Citroen still sell these new?

Any help with part numbers or suppliers would be greatly appreciated.

If I bought second hand, can they be used again on a my car or are they coded to the original car?

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Re: Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by jamescarruthers »

Hmmm I seem to have found the answer here on this thread:
viewtopic.php?t=54418

Basically there is a later ECU which is able to do the older and later Eolys systems. One is on order now, 2 nd hand, to see if the system comes back to life and the exhaust doesn’t get clogged up again.

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Re: Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by GiveMeABreak »

1525AZ is the latest and last incarnation of the Marwal Additive ECU for this vehicle James. £280.03 from Citroen new.

Do be aware that these early and separate additive ECUs very likely fail at the time of refilling the additive tank - specifically when trying to reset the additive counter. Common issues are failure of communication with the additive ECU, so it can't be reset. Later systems do away with them and the function is incorporated into the engine ECU.

So the point being that there is likely to be a much higher risk of failed units on the market that have been removed that won't show a problem until the attempt is made to reset them using Lexia. I hope you manage to get one but it will of course need resetting once fitted - so I would get them to check the success of that operation first before re-assembling.

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Re: Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by jamescarruthers »

Ah yes, resetting the Eolys is exactly what they are trying to do at Chevronics.

Is it too optimistic to hope that the later design of software has a better chance of being reset?

Luckily the second hand part was only £20 so it is worth a go for now. Fingers crossed their Lexia can talk to it.

I am a few steps away from ordering one of those recoded engine ECUs from eBay that gets rid of the DPF and EGR and cross my fingers for future MOTs.

What do people think then, £280 for the new additive ECU or a bit more for de-DPFing the car?

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Re: Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by GiveMeABreak »

No - don't do it - it is illegal to remove emissions devices for vehicles used on public roads in the UK and most of the EU.

We do not allow any advice on removing emissions systems for this purpose on the Forum for this very reason, so please don't ask for it :wink:

These 'remaps' are for people that have removed their emissions equipment. This will invalidate your insurance as the vehicle no longer meets it's original certification, so back away. People are being saddled with large bills as they are finding out previous owners have done similar things and their cars no longer pass the stricter emissions tests.

Remapping the ECU will just prevent warnings - but will not prevent blockage and engine problems as a result when the DPF can no longer regenerate with those systems still in place. This can cost a lot to rectify and will no doubt cause you additional engine running problems.

As for the additive ECU: The software won't make a difference - that was just to accommodate different fluid changes from the older Eolys DPX42 to the Eolys 176. It's one of the reasons they were dumped in favour of later engine ECUs doing the job. Euro regs also became stricter requiring emissions equipment to last longer - so with these ECUs failing at top up time, it's probably another reason they removed them with.

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Re: Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by jamescarruthers »

Ah okay, understood. TBH I’d rather have it working properly than being modified so won’t discuss that here again.

I’ll report back if this gets solved with a second hand Eolys ECU. If Chevronics have checked everything else out as working that I guess I don’t have much choice but to buy a brand new one. It should last until the end of the life of the car at the rate the last one did anyway.

Wish me luck!

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Re: Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by GiveMeABreak »

Yes, once you've topped up the fluid and managed to get the Additive ECU reset, you should be ok. Some of these worked ok - My Marwal EAS200 was fine on my C5 MK II when I had that topped up - it's the earlier ones that suffered the most by all accounts.

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Re: Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by jamescarruthers »

Latest report from Chevronics. The new ECU seems to have restored power to the pump but pump isn’t working.

I’m sure they are pretty smart but here is their report in case anyone has anything to add:
The technician has replaced the additive ECU that you have supplied and we now have power to the unit. Unfortunately the pump on the tank is not working. We have got power going to the pump but it seems to be blocked. Unfortunately we can’t strip this down as it is a sealed unit. We believe that where the tank has been emptied, the small amount of additive fluid in the tank can turn toffee like when dried out so we believe that his has blocked the pump.

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Re: Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by GiveMeABreak »

Hi James

Are your mechanics aware that there are 2 processes that need to be completed when refilling the additive tank?

1) The Fuel Additive Circuit needs to be primed or it may not work.
2) The Additive ECU counter needs to be reset.

Both these functions are completed using Lexia diagnostics. Resetting the counter alone is not sufficient - especially if the tank has been allowed to get too low.

Both these functions are official Citroen requirements.

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Re: Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by jamescarruthers »

I don’t know, but I will pass this on for sure. Thank you.

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Re: Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by jamescarruthers »

Just closing this post down now. Chevronics got the FAP system working by using a later compatible module part number 1525AZ and a replacement tank with a working pump in it.

All parts second hand from Edwards & Sons. First tank had been drained and Eolys went hard and pump wouldn’t come back to life. I went and personally picked up a wet tank, freshly removed, and carefully took it to Chevronics to complete the work.

Good work carried out by Chevronics too.

Old C5 lives to fight another day!

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Re: Eolys FAP ECU Compatibility - 2001 Citroen C5 2.2

Post by GiveMeABreak »

Well done - that's also a reason of course - when it gets too low it can seize. There are some unscrupulous people who reset the counters without putting any fluid in - just to move the car on. Really annoying.