Webasto Thermo Top EVO Aux Heater T6.1 Test run w/OBDeleven

FWhite

T6.2 skipper
VIP Member
T6 Guru
Hi all,
I am looking specifically to the T6.1 and the OEM Webasto Aux heater.
Is there a way to run a full test cycle for the heater from OBDeleven Pro (or even VCDS)?

Like to have it start up, run the fans and the pumps, warm up the air inside the Bus for some 10 minutes?
I mean with the ignition key ON (probably necessary) but the motor NOT running and the environmental conditions not completely met (i.e. T > 5 C)?
I have seen a lot of diffent items inside the Heater Control Unit, but I am not sure what they do and I reckon it is easy to mess the Webasto up with the wrong command or sequecence of commands.
 
Hi Oldie, thanks for the info.
I assume that such WTT 3.7 is a Webasto proprietary SW with its own licensing dongle. That you have available of course. It will cost something, of course, and maybe it is even available to the general public for sale. Maybe not.

But this is not the topic at hand.
I have posted here in this section to see if anyone know how to do such test with one of the common VAG tools.
I mean test at the car level, since this Webasto is an OEM configured device, factory integrated in the car, with specific FW, interfaces, etc.
It may be possible. Or not. That is what I am asking.
 
Under "Output tests" you can safely test individual components: combustion air blower, cabin blower, etc. Unfortunately in the OBDeleven it's not possible to set up a live data measurement at the same time (VCDS can).

Like to have it start up, run the fans and the pumps, warm up the air inside the Bus for some 10 minutes?
I mean with the ignition key ON (probably necessary) but the motor NOT running and the environmental conditions not completely met (i.e. T > 5 C)?
I would try under "Basic Settings" - Heater operation...
I'm not sure it would run the cabin blower though - unless it's the "parking heater" configuration - then you would have a button to start the heater.

What are you trying to achieve? Or just experimenting?
 
Hi mmi, thanks for the hint.

I did not go through basic settings, I went directly to adaptation and long coding. I will have a look then.

Why...
I am not sure the whole thing works at all, for the little use it can have.
I get no errors, sometimes OBDII live data says it is active, but the van doesn't warm up any faster than my 20 Y/O A Klasse. That small one will tip with an elk, well, yes, but could cook one inside in 10 m!
On the Bus, with the TDI on, even at zero C or less, the Webasto is so silent that i cannot hear it. If it works at all. I do not see any evident smoke coming, that gets covered by the TDI smoke and stink. I have not a private parkplace or garage, so rolling under the van on the public road at minus something is not my first priority. Besides it is forbidden. So I should wait for a very cold and wet day without wind maybe. But here usually when it is cold it is also dry and windy.
A proper test with the TDI OFF should help to understand better.

I want also to gain knowledge about how it works with the pumps and all the fans.
My one is an AUX Heater on a entry level 9 seater 6.1 DNAB Bus (shuttle in UK?). It has the secondary AC and heater for the rear seats with basic overhead panel. Common configuration for countryside and construction workers transport here.
For the moment I have seen no proven upgrade that could let me use the Webasto as a parking heater without losing the secondary AC and heater function and adding redundant wiring plumbing pumps and fans and a lot of useless duplicate work. Maybe Danham has a praticable solution, but no one is sure it works in my configuration. Haven't seen one on this forum at least.

So yesterday I was out of the hotel 5 a.m. at -5 happily hand scratching out the ice because I did not want to wake up all the people above with my TDI engine running cold. But I have a diesel heater. It is very cheap I think, to the point that the seller didn't bother to tell me it was there. Quite useless, if you ask me, though.
 
Hi,
I have the same problem.
I have a 2020 T6.1 9-passenger van. It's equipped with a Webasto 5Q0.010.014.D auxiliary heater.
The basic version has no remote control or control panel. It should turn on on cold days and warm up the car.
I have no errors, but the device doesn't turn on on cold days.

Tested with a Thingdiag tester. The tester has the following options:
Service start of the auxiliary heater (it works, turns on the auxiliary heater and heats to 90°C in about 10 minutes when stationary).
Production start (it works, turns on the auxiliary heater briefly, then turns off the test, results are OK. No errors recorded.)

All temperatures are comparable to actual outdoor temperatures. Tested at temperatures of -2 to +3°C.
I don't know what the problem could be that it doesn't turn on automatically on cold days. What controls the control? The engine? Or perhaps the climate control panel?

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I don't know what the problem could be that it doesn't turn on automatically on cold days.
How do you know it does not turn on?

The heater can be interrogated for quite a few status items which relate to
- switch-on conditions
- start inhibit conditions
- heat request condition, etc.

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What controls the control? The engine? Or perhaps the climate control panel?
It's the HVAC controller
Do you have enough fuel (no fuel light)​
Cabin blower turned on​
Cabin temperature setting high enough​
Engine running.​
 
I don't see a command to turn on the auxiliary heater in the parameters. It seems to me that all the requirements are met. I've tried all the options, even heating the windshield and mirrors.

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Interesting. Referring to post #5, I’m also a little underwhelmed by the heater and couldn’t convince myself it works.
External temp was zero deg.
Engine started. No evidence of exhaust smoke around front wheel area.
I thought I could hear a slight “roaring” sound.
Van didn’t exactly warm up quickly!

I will check with VCDS next time we get a cold spell.

Question. Would it be as simple as adding a switch in parallel with the temp sensor to force the heater to fire up?
I’ve done this on my T4 so I can start the heater regardless of ambient temp.

Not surprisingly, the T4 heater makes a real difference to engine warm up time.
 
Worth noting, re heater exhaust smoke, I also fired up the air heater to see if those fumes were visible in the cold air. They weren’t but the heater was working.
 
I thought I could hear a slight “roaring” sound.
Well, no. Not really possible to hear when engine is running. However, switch off the engine after 3 minutes and step outside on the left side of the vehicle. You'll hear the heater shutdown as it gradually cools down the heater.
 
I'm wondering why the air conditioning panel isn't sending a command to turn on the auxiliary heater. Could it be a problem with the air conditioning system?
 
Well, no. Not really possible to hear when engine is running. However, switch off the engine after 3 minutes and step outside on the left side of the vehicle. You'll hear the heater shutdown as it gradually cools down the heater.
The only unavailable pre-condition to switch-on the heater looks like it is
- motor running.
Is that a message coming on the LIN bus?
Anyone knows more about that?
 
The only unavailable pre-condition to switch-on the heater looks like it is
- motor running.
Is that a message coming on the LIN bus?
Anyone knows more about that?
I would say - it's commanded by 08-HVAC - thus over CANbus

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I was successful.

I reset the air conditioning panel to factory settings and all settings (I'm not sure if this was necessary). Then I started reconfiguring the car's preheating.

Now, the effect is that after starting the car, the auxiliary heater turns on and quickly heats the car. A side effect is that the air conditioning doesn't work, the AC button doesn't light up, and I get an error (first-time compressor activation). I hope it's just a configuration issue and I can fix it.

I don't know who changed the configuration or when, because it's been there from the start. I'm the second owner. I'd be careful next time I reset to factory settings. First, I'd try changing the configuration without resetting.
 
On a slightly related note I had the door autolock on my T6.1 stop working at some point even though it was set in the menu. I toggled it off and on again in the menu and it worked again.

I think it's always worth checking settings (and toggling them) as an easy fix first.
 
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