Mercedes w212 e220 BlueTEC adblue

[Marex55]

Hello all.
Hoping for help and advice...
I have w212 e220 2016 with adblue tank in rear.
Few days ago it stopped working with miles counter on after adblue refill hoping engine light will go off but it didnt.
After few inspections it looked like adblue crystals are in present around harnesses.
What are the chances it needs just new loom wiring and all should be good to go or problem could be worse like burned ecu etc?
Just to notice all happened after subwoofer was wired few days after. Can vibration finished corroded wires or it could kill something in adblue tank etc?
On scanner was showing 0 adblue
And couldnt remove codes or reset anything.
Now its deleted in ecu because of limited miles hoping get some advice if i even should start going deeper to sort it out or just leave deleted..

 

[rf065]

Save yourself and your wallet a world of pain, keep it deleted and enjoy how the car should have been from the start.

 

[Marex55]

Save yourself and your wallet a world of pain, keep it deleted and enjoy how the car should have been from the start.

My biggest worry is what impact it could do to dpf and all exhaust system in long run. Does adblue get injected in dpf to keep it clean? Can it get clogged? I do mostly city runs..

 

[rf065]

My Adblue & EGR was deleted last September, the car runs better than it ever did before and continues to regenerate the DPF as normal. Adblue does not clean the DPF, it might make the regen cooler by injecting adblue but it still regens without it. Adblue is an ill thought out system that will cost you many £thousands over the coming years it you want to keep it working.

 

[Bendo]

My Adblue & EGR was deleted last September, the car runs better than it ever did before and continues to regenerate the DPF as normal. Adblue does not clean the DPF, it might make the regen cooler by injecting adblue but it still regens without it. Adblue is an ill thought out system that will cost you many £thousands over the coming years it you want to keep it working.

Nonsense. Adblue does a great job at doing exactly what it was designed for. Getting rid of NOx and therefore helping to avoid making life misery for those with asthma.

But yes keep deleting emission control systems so we can all be subject to more and more reduced speed limits to improve air quality.

 

[markjay]

My biggest worry is what impact it could do to dpf and all exhaust system in long run. Does adblue get injected in dpf to keep it clean? Can it get clogged? I do mostly city runs..

AdBlue won't affect the DPF, but the city runs will. If your engine doesn't get to regen frequency enough, then the DPF will get clogged (with or without AdBlue). If this is your scenarit, then maybe you should consider a petrol car, or better-still an EV, instead of a Diesel car.

 

[Marex55]

Im not against adblue i just had to remove it few days ago due to mile counter just to be able use car..
Just hoping it could be easy fix as corroded harness. The connection pins looks ok just the harness connecting to ecu was all cover in crystals of adblue.
Maybe even hopping anyone around essex had chance changing harness and getting it fixed. Other possibility subwoofer made some dirt or crystals loose in tank and blocked nozzles etc or killed tank level sensor or not likely?

 

[markjay]

The AdBlue level sensor uses ultrasonic detection, but I don't really see how it would be affected by the subwoofer.

 

[Marex55]

Update.
I talked with the guy who installed the subwoofer saying few days before all issues started. He admitted he had ground cable shorted but denying his fault because when i took car was no engine lights or errors. Now im pissed of over the moon.
Could it damaged ecu and error came up few days later?
Would ecu replacement sort out or looking in more issues..

 

[DSM10000]

Update.
I talked with the guy who installed the subwoofer saying few days before all issues started. He admitted he had ground cable shorted but denying his fault because when i took car was no engine lights or errors. Now im pissed of over the moon.
Could it damaged ecu and error came up few days later?
Would ecu replacement sort out or looking in more issues..

Get it properly diagnosed by an MB specialist.

Throwing random and expensive parts at the problem is unlikely to fix it.

 

[markjay]

...Throwing random and expensive parts at the problem....

Aka parts darts

 

[markjay]

Im not against adblue...

There's no easy way of saying this... The AdBlue system is inherently problematic. You may fix it now, but something else will crop up later. And it's never a cheap repair... Sorry if this isn't what you wanted to hear.

 

[Tonygw]

Does the ad blue system have to be mapped out?
Does it affect the MOT?

If its easy to do seems like a no brainer to me and get it deleted.

 

[Marex55]

Does the ad blue system have to be mapped out?
Does it affect the MOT?

If its easy to do seems like a no brainer to me and get it deleted.

Its mapped out for now to get rid of miles countdown...

 

[Marex55]

Is there any way to take unit and check is it damaged anyhow without going to MB and keep spending money for nothing
Like with multimeter?

 

[markjay]

Is there any way to take unit and check is it damaged anyhow without going to MB and keep spending money for nothing
Like with multimeter?

Whoever mapped-out your AdBlue, should have the tools required (STAR diagnostic) to check the codes.

Alternatively, take the car to an independent specialist (not the dealer).

 

[Marex55]

Whoever mapped-out your AdBlue, should have the tools required (STAR diagnostic) to check the codes.

Alternatively, take the car to an independent specialist (not the dealer).

I mean not the codes. The actual adblue ecu in the trunk test

 

[rf065]

I mean not the codes. The actual adblue ecu in the trunk test

Even if you fix it now, it could cost you over £1000, then another part will go in 6 months time and cost the same amount. It's never-ending and costs plenty every time.

 

[markw221]

The environmental impact of mapping out has kept me persevering with attempts to fix a similar problem on my W221. Mine was fine till the first time I refilled the tank. I use a YOUCANIC diagnostic tool and had to reset the level sensors using this tool for the three fill sensors in my tank to register 'WET WET WET'. Since the refill I’ve had regular adblue warnings 'check manual' with the Amber eml. I get no codes on my diagnostic, the faults usually take 100+ miles to come on, rarely remain between drives and often disappear during the course of the same drive. I’ve only tried low cost solutions. I found heavy crystal clogging where the injector connects to the exhaust so I disconnected and cleaned this area carefully with warm water but faults continued. I’ve tried an anti crystallisation additive. I’ve replaced the adblue in the tank with a fresh batch because it needs to be a fresh batch stored out of sunlight. I've replaced the internal parts of the metering device. None of these has cured the problem but as the fault warning generally clears itself and is definitely injecting adblue ( tank level going down slowly) I’m resisting the temptation to map it out. It’s very annoying though and I understand why many give in and map out. Good luck with yours.
My next step is probably to go to a full Merc diagnostic at an independent to see if there are stored codes my YOUCANIC tool doesn’t show