No Flames: Error Code 01406 Explained

Hello.

VW Passat, year of manufacture 2010, TDI engine, 140 horsepower.

In the control unit (1 of the auxiliary heater (part number MWB004), one can observe the control signal for the glow plug.
With the actuator diagnosis, I can see the resistance value of the glow plug. How do I know if it's defective or just dirty?
The background is that the car is still under warranty, but the dealer wants to remove the auxiliary heater because they need to inspect it to determine what's broken.
It was thought that the diagnosis could help narrow it down.

Best regards,

Hi!

If the resistance value is okay, maybe around 4 ohms, just guessing.
and the corresponding current is flowing (using a clamp meter).
Then the spark plug is okay.

I'm more familiar with the fact that auxiliary heaters tend to be unreliable.
Inside, there's a wad of steel wool where the combustion takes place.
Over time, it will accumulate residue from combustion.
It can be replaced or cleaned.
Then it usually works again.

But if it's still under warranty, you should definitely get it fixed.
Don't try to fix it yourself.

Okay, thank you.

I want to have it done, but the issue is that the dealer might try to sell me something else. That's why I wanted to check it myself using VCDS.

Steffen G wrote:

There is a bundle of steel wool inside, where the combustion takes place. Over time, it will accumulate residue from burning.

Hi Steffen,

This concerns a MJ2010 vehicle. It already has the Webasto TT-V installed (which has been available in the 3C series since its introduction in 2005). This unit uses a Venturi burner (similar to an oil heating system at home) and no longer uses the steel wool bundle type of burner like the Thermotop Z/C.

Greetings.
Sure.

Here is the translation of the text from German to English:

"Guste" means "gust" in English. It can also be used as a verb, meaning "to gust."

It looks like that.
The burner in the heating unit needs to be replaced, including the igniter. This is a component. Please have this done now. During the winter heating season, there can sometimes be issues with spare parts availability.
Expanding the heating unit is necessary for this to work; there's no other way. Your dealer can connect the two water hoses, allowing you to continue on your journey while they overhaul the heating unit at their convenience.
Perhaps the dealer will even exchange the entire heating device for you if you're lucky.

Okay, thank you.

Well, I hope he replaces the entire combustion chamber because I had it replaced in January 2013 due to similar symptoms as now. The only difference is that the SH (presumably a component) used to lock up constantly, which isn't happening in this case.

Best regards,

Hello.

Okay, the auxiliary heater has been replaced under warranty. Now I wanted to disable the supplementary heating function... it's already set to zero as expected.
So, it seems like it's always running... Now my question is: Can you change the temperature setting within the measurement blocks so that the auxiliary heater only turns on at 95°C?
or another option?

Best regards,

Glatze wrote:

Is it not possible to change the temperature setting within the measurement blocks so that the auxiliary heater only activates above 95°C? or another possibility?

No, it always runs when the outside temperature is below 5°C, and you will still notice in the winter that this is a good thing...

Seriously: At -5°C, the box will heat up relatively quickly. After winter, at +5.5°C, you'll be surprised by how long it takes for the car to warm up again. The TT-V isn't nearly as prone to this issue as the old steel wool sponge from Z/C (even though you might be experiencing something different right now).

Greetings.
Sure.

Here is the translation of the text from German to English:

"Guste" means "gust" in English. It can also be used as a verb, meaning "to gust."

Yes, she is vulnerable.
This is the third one (two of which were replacements under warranty) with 180,000 km on it, in the last 5 years, and 90% of that mileage was highway driving.
And it always runs for at least 30 minutes in the morning and evening, starting from when the vehicle is started.

Best regards,

Okay, I've come up with something, and I hope you can help me implement it.

I want to install a relay that interrupts the power supply to the auxiliary heater when the ignition is turned on, and reconnects it when the ignition is turned off.
I wanted to achieve this by connecting it to the positive terminal or fuse of the auxiliary heater.
Is that a possible option, or do you have any other ideas?

Best regards,

Hey Klaötze!

Glatze wrote:

... would that be a possibility, or do you have another idea...

It would be nice, but I don't understand either the problem of a working heating system or the mental tricks used to numb/kill someone by accessing them through the nipples .

How about simply taking the safety OFF!
...or, if necessary: Unplug it!

While some people would be thrilled with such a great and effective auxiliary heater, tastes are known to vary .

Best regards from Munich!

In the past, for example in the Sharan 7M, auxiliary heaters from companies like Eberspächer were installed using standard 12V wiring. See:
https://www.sgaf.de/content/abschalten-zuheizer-hilfe-taxischalters-253045
With your model, you immediately get an error message indicating a power interruption, followed by a locked device. With the Touran with the TTV system, simply setting the Climatronic to "Eco" mode was enough to put the auxiliary heater on pause. Try that when it gets cold again.

Glatze wrote:

Hello. Do not change the temperature of the measurement blocks, so that the auxiliary heater only activates when the temperature reaches 95°C. best regards

No, why would it? At a cooling water temperature of 95°C, the preheater is off because there's nothing left to heat up..

@DieselBear30x

I know what the auxiliary heater is for, but I don't need it because I drive 120 km each way every day, and 100 km of that is on the highway, so it reaches its operating temperature and maintains it.
But I've already had my third car inspection in 4 years, and it cost €680 including installation, which I would have had to pay myself.
"I think it's absolutely ridiculous that this thing is starting up again just because you have to drive another 7 kilometers."

@steffen, something's not working with "econ".

Best regards,

Glatze wrote:

I want to install a relay that interrupts the power supply to the auxiliary heater when the ignition is turned on.

Sure, you can turn off the auxiliary heater by interrupting the power supply. HOWEVER: If the auxiliary heater has already been running, it may not shut down properly. Normally, the pump and combustion air blower continue to run for a certain period after the main function stops. I cannot say whether this "after-run" is necessary to prevent damage due to localized overheating.

However, I wouldn't risk it. Therefore, either permanently disconnected or permanently connected.

Greetings.
Sure.

Here is the translation of the text from German to English:

"Guste" means "gust" in English. It can also be used as a verb, meaning "to gust."

Okay, thank you.

That's true regarding the afterglow, I hadn't thought of that.