DPF ash level 100% - Berlingo

[acealfa]

Hi all,

Decided to read for any fault codes on a family members van (B9 Berlingo 1.6Hdi). I was greeted with P1445 code saying DPF must be replaced. There was no engine warning lights. I know a little bit but I'm not an expert in DPFs.

Apparently ash level is 100% but I understand this is just a calculation rather than fact. The mbar pressure is 2-5mbar on idle & 60mbar at high RPM so isn't too high but I believe the DPF will no longer regenerate now?

Is it safe to just tell the ECU the DPF has been replaced so it will continue to regen or is it just best to have properly cleaned out or replaced? I'd assume if the pressures went out of range it would trigger a warning light?

Thanks

[Dynion Araf Uchaf]

I watched the O’reillys YouTube on something similar with a PSA car. I think there is inbuilt redundancy when the dpf gets to a certain mileage and it sets it to mileage left of the dpf to zero.(distance remaining before particle filter replacement) You can programme it out and get the fault code removed and the car working again.

[acealfa]

Cheers, just watching one of his videos now. I never knew there was an addictive tank for the DPF, what a faff!

[Steve H]

You don’t need to start removing fault codes, that would be a mapping process. Just tell it that you have fitted a new dpf as you suggest in your OP.

Might be worth checking the level in the additive tank if you don’t know what it is but that would give a different code so not likely to be an issue here.

[Otispunkmeyer]

Dynion Araf Uchaf said:

I watched the O’reillys YouTube on something similar with a PSA car. I think there is inbuilt redundancy when the dpf gets to a certain mileage and it sets it to mileage left of the dpf to zero.(distance remaining before particle filter replacement) You can programme it out and get the fault code removed and the car working again.

Most likely this is the case.

But just for further info. Ash build up is generally built into the sizing of the DPF, they should be "over-sized" to account for ash building up over the lifetime of the vehicle. It won't completely block the filter for a long time, but it would increase the backpressure which might cause other issues with EGR and things. But as you say its going to be a pre-programmed time based on testing, they don't really have a good way to monitor this stuff beyond delta pressure signals.

The other thing is ash cannot be burned away, its effectively the products of stuff that has already been burned. So it will just continue to accumulate.

[MB140]

Dynion Araf Uchaf said:

I watched the O’reillys YouTube on something similar with a PSA car. I think there is inbuilt redundancy when the dpf gets to a certain mileage and it sets it to mileage left of the dpf to zero.(distance remaining before particle filter replacement) You can programme it out and get the fault code removed and the car working again.

Yep I’ve seen that video too, effectively at a certain age or mill age the PSA group have coded it into the car’s computer to tell you the DPF is full and needs replacing regardless of the condition.

Very very naughty in my opinion. Nice little earner for them as well replacing all those DPFs. I’m sure in the video I watched he just effectively told the car the DPF was new and hey presto apparently the DPF is no longer 100% full even though nothing has changed.

[Otispunkmeyer]

MB140 said:

Dynion Araf Uchaf said:

I watched the O’reillys YouTube on something similar with a PSA car. I think there is inbuilt redundancy when the dpf gets to a certain mileage and it sets it to mileage left of the dpf to zero.(distance remaining before particle filter replacement) You can programme it out and get the fault code removed and the car working again.

Yep I’ve seen that video too, effectively at a certain age or mill age the PSA group have coded it into the car’s computer to tell you the DPF is full and needs replacing regardless of the condition.

Very very naughty in my opinion. Nice little earner for them as well replacing all those DPFs. I’m sure in the video I watched he just effectively told the car the DPF was new and hey presto apparently the DPF is no longer 100% full even though nothing has changed.

Its not really that naughty, its just conservative and pragmatic.

ECUs don't have any real way to detect what's in the DPF. The very cheapest way to have some kind of feel for it is a pressure port pre DPF connected to a deltaP sensor that has its other side referenced to ambient.

Inside the ECU will be a very basic soot load and ash loading model that is based on a few metrics like running time, fuel used and that delta pressure signal. A lot of work goes into trying to get some kind of accurate soot loading model, but its not easy. At the end of the day they're going to err on the side of caution and go with very conservative limits and measures. It'll depend on the lube oils and fuels used as well and these can't always be guaranteed to be of known quality. A particular difficulty is modelling the amount of soot/ash that ends up in the DPF from things like cold starts.

We're actually doing this work right now with an OEM and it requires some very specialist (and expensive) equipment for measuring soot in real time and even then, they don't truly know what has happened until we dissemble the exhaust system and weigh the DPF can. Its very time consuming and you're looking for grams difference when weighing a 20-25kg part (its a heavy duty application so its bigger than a passenger vehicle setup).