S204 C250CDi: DPF Restricted - Do I need a STAR diagnostics?

[DucatiEVO]

What you need them to find is the reason it doesn’t complete a regen.
It can be a number of things. In my case a while ago it was a 12v battery issue. A new battery sorted it

A Mercedes Indy said the DPF had to come off and be cleaned etc etc etc and some other stuff blah blah circa £700.

The diagnostics thing I use quite clearly said “ reason for non completed regeneration - battery voltage too low. “

I’d been delaying changing the battery as the car was in constant use. After 3 days of no use the battery was flat and the car wouldn’t start.

Basically you need to find the root cause as resetting things is a short term thing

The Autel AP200 is their cheapest diagnostic machine and for me it’s been invaluable. Below is a screen shot of the report it generates showing the last 16 regen attempts. Some fail and the reason is shown. It’s an a very useful tool which has saved me hundreds of pounds. It also shows live data such as fill level, exhaust pressure, DPF temperature etc.

Worth remembering if there are and stored and current codes triggered that the car won’t regen. And an active code doesn’t always give a CEL on the dash.

So I brought an Autel AP200 (I have to say the app isn't great (let alone having two apps for the same job), however I can't get it to load/connect up the Service Options properly, I always end up at the menu below, and none of the options appear to load up (just sit on the loading screens).

Do you recall what option you chose?

I fear I'll be sending this back, and going the old 'Indy' route still.

Thx

 

[sautah]

You need to load the “Benz” app plugin and then do the automatic VIN selection and then the automatic scan of the whole car.

Once it’s scanned all the modules select the top one “digital motor electronics “ and then live data. The DPF menu is there

It takes a while but the app is prettty self explanatory and although simple looks wise has everything you would need

 

[DucatiEVO]

You need to load the “Benz” app plugin and then do the automatic VIN selection and then the automatic scan of the whole car.

Once it’s scanned all the modules select the top one “digital motor electronics “ and then live data. The DPF menu is there

It takes a while but the app is prettty self explanatory and although simple looks wise has everything you would need

Yup, I loaded the 'Benz' plugin, and it detects the VIN, but after choosing the Digital Motor Electronics, it fails the detection and presents me with the menu options listed previously....

 

[sautah]

You’re choosing the modules manually.

Start from fresh by closing the app. It’s really not that difficult. Choose automatic scan

 

[sautah]

 

[DucatiEVO]

You’re choosing the modules manually.

Start from fresh by closing the app. It’s really not that difficult. Choose automatic scan

View attachment 158315

Yes I do the automatic scan above, and it's after that point it fails with a can't detect xxx and gives me the list of what engine/code to choose.

 

[sautah]

 

[sautah]

When the scan has finished all modules select the top one CDi motor electronics

 

[sautah]

It takes a while so be patient

 

[sautah]

 

[sautah]

 

[sautah]

There you go. I’ve just sat in the car and screenshot this for you so hope you get to the bottom of it.

 

[sautah]

Have you got the ignition on ? All dash lights etc on but engine not started ?

 

[DucatiEVO]

Thanks for that, still no luck sadly (tried ignition on engine not running and running.

You can see the below stages I captured - it works up until the 3rd picture and scans the Motor Electronics, then I get the list (in blue text) that it can't find the Motor Electronics and to choose from the list, so I chose the same as you (I have tried others options with no luck) 'CDID2' and then it scans again, last two pictures, but I waited 7 minutes (see highlight in yellow on screen shots), and gave up in the end.
How long does it take your one to scan the last screen - I can't believe it would be over 7 minutes?

Thx

 

[sautah]

It does take quite some time ……. Not timed it though. I usually make a cup of tea.

 

[DAMO71]

Hi All,
I have a very similar situation with my C220D 2015 bluetec auto. Since I bought the car in 2023 I’ve had the downstream nox sensor replaced twice and the upstream once. I’ve had the DPF professionally cleaned but I still get the same issue that on days where I do several short journeys and the stop/start system is on, when I come to a junction and the engine switches off, when I come to accelerate away it won’t change out of 1st until it hits 3000rpm, same with 2nd to 3rd. There is no engine warning light and by pulling over and turning the engine off for 30 secs and back on car drives fine again. It’s really frustrating. Apparently it’s common in mercs of that 2014/2017 era to do it, they don’t like town driving. Mines only done 76000 and 95% of the time runs with no issues.