Problem with electricity. Auxiliary heater (G6 GTD) (Solution)

Hello, I've been having trouble with my auxiliary heater for over a year. The device stubbornly refuses to work, and neither I nor the workshop have been able to fix the problem. Last year (in March), my from VW instructed them to re-flash the climate control module, and after that (much to my dismay), the device worked until now, when it conveniently stopped working again just in time for the cold season. In my case, the auxiliary heater doesn't turn on at all. The workshop told me: "It's working, it's still too warm (4 degrees), and the efficiency of modern diesel engines is such and such." When I use VCDS to access the actuator diagnosis, the relay for the auxiliary heater turns on briefly, then switches off again after 2-3 seconds. Last week, the workshop completely replaced the auxiliary heater, but without success. Then, the master technician called me, saying they wanted to re-flash the software of the climate control unit. I went to the workshop, and after about three-quarters of an hour, the master technician came and said: "Everything is okay." I got back in the car, set the climate control to "defrost windshield," but there was no power-on sound from the auxiliary heater (you can usually hear the clicking of the relay clearly), and the engine speed didn't increase. The master technician's statement: "It's still warm (5 degrees)." So, I went home. Yesterday, I connected VCDS, and it turns out:d they didn't flash anything; it still shows one flash process (from March). My guess is they just checked to see if there was an update and that was it. Now I feel completely foolish, I've already taken it to the workshop 8 times because of this thing, and it still doesn't work. I'm open to all suggestions, except: Don't get a parking heater installed!

Hi,

Is there a difference between the actuator tests "relay for low heating power" and "relay for high heating power"? Will both of them be discontinued so quickly?

And what does the onboard voltage read during the test (measured with a separate multimeter)? Could it potentially drop significantly?

Are the fuses okay?

I seem to recall that the part is secured to the SB with some kind of thick material.

Furthermore, I think I can detect the power consumption of the interior light when it's turned on, although this might be more difficult with LEDs.

No increase in load is occurring; everything is off; climate control on; generator load at a maximum of 40-42%.

I just received a call from , and after I explained things carefully, he asked me to read out all the STG bit sequences and send them to VW. VW responded that one or two bits were incorrect, which would likely lead to the problem mentioned above.
I'm supposed to receive other software for the MSTG this week. I'm really excited to see what it is. Go and get the car back first; it's been standing there for too many days, probably around 20 .
Why don't they have an image in the database? As long as it works, that's the main thing. I was driving a VW Golf TDI the other day, and I almost cried.
I'll get back to you with an update. Until then, freezing but with consumption close to the factory specifications .

The relays for low and high heating power are likely controlled based on the outside temperature, engine temperature, time since the last start, and the alternator load, even in this model.
If it's too warm (around 5°C), the relays will not activate. Also, if the load on the alternator is too high (e.g., due to the air conditioning), the relays may also remain inactive.
What value does the MSG (Multifunction System Display) show for the on-board voltage? Is the wiring to the alternator in good condition? There's an extra port on my old model.
During the actuator diagnosis, each relay is switched on and off cyclically. Did you complete the actuator diagnosis correctly? Roger had already inquired about both relays.
It's likely that the "STG bits" refer to the coding bits. Please read out (or have read out) the coding before making any changes. If nothing was done beforehand, there is no explanation for incorrect values.
hg
Herbert.

Since the relays are switching in the actuator diagnostics but no load is being drawn, I believe the fault is more likely to be "downstream" of the relays.

Sure, here's the translation:

"So, something like that."
- Fuse
- Feed line
- PTC blown.

Keep us updated

m;

"I may not have expressed myself clearly. The actuator diagnosis is running in an 'infinite loop,' meaning it doesn't stop after the set 30 seconds, but continues until I manually end it. During the actuator diagnosis, the generator load doesn't change, it remains around 40-42%, with a voltage of 14.4-14.7 volts, regardless of whether the air conditioning is on or off. When I turn on the lights, seat heaters, and other consumers, the generator load increases to 60%. The PTC element was replaced last week, but it didn't improve anything. As you can see in the video, the relay briefly engages and then disengages after 2-3 seconds. According to the service technician, bit 06 is likely set incorrectly. Hopefully, we'll know more by Friday." Thank you all for now.

The engine control unit (ECU) controls the relays, which in turn switch the PTC heater.

If the relay clicks, then the motor control unit (STG) may have as many bits of data as it wants, but voltage *must* be present at the PTC (Positive Temperature Coefficient) resistor, and ideally, current should also be drawn.
Unless a fuse or a cable (between the relay and the PTC resistor) is broken.
Or maybe the PTC is dead.

Then, exactly the scenario you described will occur.

BTW:

I can "see" the PTC engaging even with the engine running.

Recently, I had the interior light on.
The engine started, and a few seconds later, it sputtered.
From previous logs, I know that this is the PTC.

m;

Okay, everything is working perfectly again and it's nice and warm in 10 minutes. On Friday, they finally installed a new software update on the MSTG, and now everything is working as it should. Although, some things are running differently than before. The small heating circuit is activated 10 seconds after the engine starts, and then the main heating circuit is activated after another 15 seconds. I checked, and the software version is now:

Quote:

Part number SW: 03L 906 018 BC HW: 03L 907 309 R Part: R4 2.0L EDC H23 9784

now

Quote:

Part number SW: 03L 906 018 BC HW: 03L 907 309 R Part: R4 2.0L EDC H23 7819

That means a downgrade was performed. The power consumption during the warm-up phase is now also higher, but it quickly decreases after reaching the operating temperature .

Interesting... and thank you for the feedback .