Repair Eberspächer D5WS heating control unit for Sharan

Good morning.
For the Sharan mentioned in the signature, the regular maintenance of the heating system will be due soon. The current problem is:
The heating process is interrupted in very cold weather (below -10 degrees Celsius), accompanied by previous erratic speed changes of the combustion blower motor and smoke emissions. There are various error messages related to the V6 combustion blower, which reappear even after being cleared.
Here's the translation:

"This refers to the Eberspächer D5WS heater, part number 25 2164 05 00 00. The repair is scheduled for September 4th. I will be replacing the V6 engine and, in addition, I want to check the connections on the HSG (Heater System Control) circuit board for cold solder joints or replace the entire HSG. The corresponding pins on the circuit board are known."
This time, it's not necessarily about saving money on a new heating system. However, I want to have the heating system completely finished and ready to go for the next winter by this one day. That's the goal.
Therefore, the question: Has anyone ever successfully removed a heating control unit from the mass of material it's encased in without causing any damage? If so, could you share your experiences? Or would it be wiser to order a new control unit next week and simply replace it?

Um, yes. Buy a new one. It might cost you, but you'll thank me later. You can still try to take it apart, but it won't make a difference.

Hi Steffen. Because it's so well-mixed/thoroughly combined, it will be difficult.
As far as I recall from the training, they recently switched to a different STG manufacturer because their products were starting to bloom.
Then, even if you manage to fix it, the likelihood of problems recurring during the winter is high, and trouble is almost guaranteed.
Combine harvesters break down in the summer, and SHZ (presumably a type of machinery) fail in the winter... good luck.

Manchmal muss man der Wahrheit ins Auge blicken,nützt nichts.Es bringt mir nichts wenn ich mir eine Dauerbaustelle schaffe.Das ist genau das,was ich nicht will.Und wenn was schiefgeht bin ich an dem Tag ziemlich aufgeschmissen und werde nicht fertig.Ich bestelle mir nächste Woche das HSG und nehm das Alte nach der Reparatur dann als Übungsobjekt.Die Kehrseite der Medaille ist dann,dass ich an dem Reparaturtag dank plug and play Austausch wahrscheinlich sehr zeitig fertig sein werde.
I understand. Thank you for your answers.

What does this thing cost?

To be honest, I won't know the answer until Monday when I'm back at work. It's also interesting to consider the price difference compared to a complete heating unit. It probably wasn't that expensive, and then I would have a spare unit for refurbishment/selling/keeping, and it would also be finished faster. Availability is another point to consider. However, I'm optimistic because it's not yet heating season.
I'll send you the prices on Monday.

Wenn ich es noch richtig in Erinnerung habe 250....380. In diesem Bereich je nach System.

And after over 2 hours of struggling, I had given up.

mullemaus wrote:

And after over 2 hours of struggling, I gave up.

I believe every word of that. I was also prepared for the fact that it wouldn't work and had already planned to get a new HSG. And even if the resin degrades, it's likely that the circuit board or components on it will be damaged (even more).
Someone had planted a seed of doubt in my mind, and because I'm an optimist, I had calculated – no, hoped – that there was a small chance I wouldn't have to buy the HSG (presumably a company or property).
It's not a big deal; if you have an older auxiliary heater, you just have to live with it. I'll just deal with it like this.
Unless JE can't deliver (which is unlikely in September), I'm considering getting a new heating unit. The new blower motor is already here. I'm also going to proactively replace the flame arrestor. The ceramic igniter is already installed.

@Klaus
The item costs 229 euros net (before tax) without any discount. I ordered it today.

Steffen W wrote:

... 229 netto...

(That price is outrageous for a bit of electronics with a material value estimated at just 5 euros.)

DieselBär30x wrote:

Steffen W wrote: ... 229 netto... (Such a price is outrageous for a little bit of electronics, considering the material value is estimated at 5 EUR *note*)

You are right, but the software doesn't write itself either.

"...and what exactly is the customer paying for when they purchase a new, complete Eberspacher system?"

You mean retrofitting, not replacing the heating devices?
Heating device, water pump, fuel pump, control panel, fuel tank sender, installation materials, and labor costs.
SC heaters have the two pumps integrated internally within the heating unit. This version requires more space and saves installation time, but it is not cheaper. The biggest price differences are found in the control panel and the heating output. A timer is relatively inexpensive, while a remote control is considerably more expensive.
It will definitely cost four digits for end consumers, depending on the model and configuration.

Through a friend, I heard that another acquaintance of his heated up the defective control unit (STG) of a D3WZ in a water bath at moderate temperature, and after that, the control unit started working again.

I have no idea if that's true.
At least trying to fix a truly defective control unit won't leave you any poorer...

Yes, because water evaporates, and the older steam generators probably had a problem with that.
Don't forget to waterproof it afterwards.

"You're right, Michi, but I want to have it fixed by Saturday. And there are other possible causes besides water damage. The heating system will probably work perfectly after the oven incident until temperatures drop to -20 degrees again, and then it will turn out that it would have been smarter to replace the unit because it's faulty anyway, and I'll be starting all over again in the winter. That's what I want to avoid right now. And with particularly bad luck, this specific part might not even be available in January because there are other Sharans or T4s with broken heaters, and Eberspächer will be in high season then."I'm going to replace the control unit and the engine, and hopefully that will get rid of those annoying heating issues for now.
I'm sure I'll be making various attempts at modifications and experiments with the old ECU.