Where is the DPF ECU?

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Bandit12
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Where is the DPF ECU?

Post by Bandit12 »

Hi Guys

After lots of fiddling I've successfully removed and flushed out the DPF filter with the acidic car wheel cleaner and boy was it clogged :shock: The cleaner just sat at the top like oil on water with no sign of going through the filter. It took a couple of flushes and use of a jetwash to clear it out. All sorted and back on the car and running smoothly with no more error messages concerning filter clogged etc:-D

Only one error message remains. Car keeps saying "diesel additive low" and I'm still struggling to tell the car the DPF additive tank is not empty. I've dipped the tank with a clean piece of bent wire and its showing between 3-4 litres but despite repeated efforts to erase the fault using lexia it just says "Fault remains" The lexia lists the fault as a "permanent fault diesel additive low"

I found a thread that suggested this is quite common and the reason maybe the DPF ECU is duff and needs replacing. Any idea where I would find it on a mark 1 2.2 diesel estate?

Failing that any ideas on how I can convince my car there is plenty of additive in the tank are gratefully received.

Cheers
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Re: Where is the DPF ECU?

Post by DickieG »

IIRC the ECU is located under the O/S rear seat or somewhere in that vicinity.
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Re: Where is the DPF ECU?

Post by wheeler »

Not far off. It's bolted to the o/s/r inner sill, pull the carpet back, there may be sponge/polystyrene covering it, small black box with a 15 or 16 pin plug.
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Re: Where is the DPF ECU?

Post by Bandit12 »

Thanks guys thats brilliant? They appear to be about £170 for a new one. Is there anyway of testing it to be sure its duff?
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Re: Where is the DPF ECU?

Post by SaabC5 »

I had the same problem, rather than spending £160 for a new ecu i just carried a bottle of eolys fluid and a pipette around in the boot, every time i filled up i put 10-15ml of fluid into the tank.
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Re: Where is the DPF ECU?

Post by Bandit12 »

Cheers SaabC5,

Does that mean that although the EOLYS tank is 3/4 full, the car thinks the tank is empty and it is not injecting anything into the DPF filter? :?:
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Re: Where is the DPF ECU?

Post by RichardW »

It's possible, which would account for the filter being blocked in a relatively short time.... SaabC5's idea sounds like a plan to me!
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Re: Where is the DPF ECU?

Post by SaabC5 »

Bandit12 wrote:Cheers SaabC5,

Does that mean that although the EOLYS tank is 3/4 full, the car thinks the tank is empty and it is not injecting anything into the DPF filter? :?:
Thats the conclusion we came to after putting the car on Lexia.
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Re: Where is the DPF ECU?

Post by Bandit12 »

Oh great :( Almost full tank of eolys for nothing then :(
i agree pippetting DPX into the diesel tank is certainly the easiest thing to do. I just hate error messages-would this error message mean an MOT failure?
I'm going to have one last try at resetting with lexia but wish to confirm a few things first.

The advice is to clear the faults on both the additive ECU and the injection ECU.

On the lexia mainpage opening the "Diesel additive function" is where the "permenant low additive level signal" is found. Is this the same thing as the additive ECU that I need to clear?

3 lines below that on the lexia is the word "Injection" is this the injection ECU that I also need to clear?

To clear these faults all I need to do is to read them then erase them? There is mention about zeroing an additive qauntity measured in grammes. I have found a page labelled in red "Permenant fault, amount of additive. Fuel additive ECU" On this page are listed the following,

ECU fault code P1442

Fault code additive system yes

total fuel additive quantity 236gramme(s)

distance travelled since last
regeneration 0km

low fuel additive level reached

distance limit reached yes


i also found exactly the same faults including the 236 grammes on a page labelled "Permenant fault. ammount of additive. Max additive level in particle filter reached. This has been sorted as I've cleaned out the DPF but do I need to reset this 236grammes as well?

3rd page lists

ECU fault code P1435

total fuel additive quantity 25 grammes

cranking phase yes

engine speed 0 rpm

low fuel additive level reached


Do I rset the 25 grammes to zero too?

Any other pages I need to be looking at for additive ammounts to zero?

Is this the 236 that must be deleted and replaced with a zero? How do I zero them? Do I just highlight using the cursor then overwrite a zero or is there another page I need to access?

Lots of info and questions there guys but I just want to be sure i'm zeroing all the right numbers and not spending £170 on an ECU unnecessarily. Lexia is not the easiest of diagnostic systems to get to grips with especially as this is my first citroen and diesel.

As always any advice is gratefully appreciated
2002 Citroen C5 2.2Hdi exclusive estate (sadly gone) :(
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Re: Where is the DPF ECU?

Post by Stickyfinger »

I had no idea what I was doing and zero'ed those numbers.....it seemed to work as no more faults came up, shortly after I trashed the car :@).....what harm can it do?, you can always reinsert the number back in was my thinking.

Have you tested/fired the "injector" via Lexia ? , you can hear it click and have a few attempts in the bank (5x I think)
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Re: Where is the DPF ECU?

Post by Bandit12 »

You do make me laugh SF :rofl2: so was the deleting of the numbers and the trashing of the car linked? Got mental pic of you tearing down some country lane dodging sheep while balancing lexia on your lap deleting fault codes-chuckle
I have done both the diesel injector and the diesel pump test but in fairness I was sitting in the drivers seat with laptop on front passenger seat and could not hear any "gentle clicking" of the injector but did easily hear the the additive pump whirring.
I'll try the injector test again and get my ear under car nearer to the eolys tank.

I'll also delete all those grammes and see what happens. Lexia is not as intuitive as some other systems i've seen and defo has a whiff of windows 95 about it :lol:
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Re: Where is the DPF ECU?

Post by Stickyfinger »

The Additive Pump....is what I was referring to as "injector"....sort of wirr-clic....for me if memory serves.....good luck and best persist then you will be the font of all for it.

Microsoft Sheep Avoider App.....works well in the lanes :)

Best of....it was all confusing to me, but I struggle opening plastic packaging without cutting myself
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Re: Where is the DPF ECU?

Post by Bandit12 »

Cheers mate and I'm heading down to Devon and dartmoor in a couple of months so will defo download that app-chuckle :lol:

As for plastic bags- they baffle me too :oops:
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