Aux Heater Fault

[Lee S]

Still haven't had chance to fault find on this one, but as the temp here dropped down to below 6 degrees I thought I'd have a quick look under the front drivers side when I started her up this evening, but there didn't appear to be any smoke coming out. The car had probably got to 90 degrees within about 6 miles, which seems normal.

Now here's the odd thing. I could have sworn blind that I had the Aux Heating and Aux Ventilation menu on the AC page of the MMI, but it's no longer there. Could this be something that is related to the Webasto not working or has it been coded out somehow? Is there any way to get this menu back up at all?

Sorry for all the questions, but this is bugging me now as I know it was all working a couple of years ago and I'm wondering if somebody (ie Audi) have screwed something up during a service or repair?

I will deffo pull the fuse and check that tomorrow and also try the aux heater functional tests when I get a moment.

Cheers all

[Mechcanico Lee]

Hello Lee , sure said this before some where search for ' definitive guide to fitting auxillary heater ' its on this site , it goes on about how to code the aux heater so you have the mmi timers and manual start functions .

Had a look on mine the other day in aux heater activations , glow plug run is there , well is on mine anyhow , feed pump run , combustion fan run its all there

[Lee S]

Thanks Lee. Will give this a go tomorrow or weekend. It's going in for a 4 wheel alignment tomorrow morning so will get that done and then concentrate on fixing this snag and the parking sensor snag. Should be all shipshape again then.

Thanks once again and I will post back on my findings.

Cheers.

[Lee S]

This gets even more bizarre. Just checked my build sticker and it doesn't have this 9M0 code:

Auxiliary heating - 9M0 - Without auxiliary/parking heater

So how can I have a Webasto fitted? Or is this a different thing?

[Lee S]

OK. So ran all the tests on this module. There were about 5 or 6 tests.. they all seemed to go through OK. The dosing pump test made the clicking noise. I then cleared the fault code and it remained clear (hooray). I started the car (AC and heated seats on, coolant < 70 and ambient outside temp about 2 degrees) and it seemed to fire up OK. Smoke from under the front of the drivers wheel. No more fault code either. The fault seems to have cleared itself. Must have been due to an extended period of inactivity I think.

I still don't have the Aux Heating menu in the MMI though, so I might look into coding that in. Would be handy just for the ventilation function to vent the interior in the summer when leaving work.

Thanks for all the input. False alarm I think... Sorry guys..

[Lee S]

I have just enabled the Aux Heating in the MMI menu and it appears to be all working.

I was a bit worried about the Aux Heater overheating and throwing a fault code but it seemed OK when it was on for 5 mins this morning. Then... and this is the odd thing... I decided to check out Module 18 again. The Aux Heater module. I went into the adaption screen to check channel 10. This is the channel that is set to '3' when you fit the circulation pump. I expected to see this set to '0'.... but no. It was already set to '3' and I was getting readings such as duty cycle % and other things.

I have NEVER set anything in here before with VCDS and I'm only the second owner with the first being an Audi dealer. Could it be that I actually have the circulation pump fitted from standard? Is there any way of telling? Noises? Measuring blocks? After running the Aux Heating there were no fault codes anywhere and the dash icons were working too. Do I have the pump?

[Mechcanico Lee]

With engine off set the aux heater to come on for a 15 min time period , if there is no pump the heater will shut down due to water temp over heat and you may here the pipe work ' thunking/gluging ' due to the aux heater boiling the still water in its own water block .

This is what my car did until i fitted the aux water pump .

[snapdragon]

Originally Posted by Mechcanico Lee

With engine off set the aux heater to come on for a 15 min time period , if there is no pump the heater will shut down due to water temp over heat and you may here the pipe work ' thunking/gluging ' due to the aux heater boiling the still water in its own water block .

This is what my car did until i fitted the aux water pump .

You are right, mine used to do do exactly that - you could hear gurgling and it would shut off and throw an overtemp code. I did some additional adaptations and now it heats the car. Even on a frosty morning it will melt the ice on the front and side windows and when you get in the car it feels warm like it was just driven and the side face vents are blowing hot air (nothing out the centres).

I will check the values and paste back in this thread. IIRC there is a residual heater pump in near the heater matrix that circulates the coolant well enough but it is not activated just by coding.

[HPsauce]

Auxiliary coolant pump, we all have it (D2's and D3's). It's the thing that stays on when you use the "rest" heating function and when it gets old/worn makes an awful noise.
Which is why mine has no power to it......

[Johnmed]

How do you enable the aux heating controls in the MMI? I had a webasto in my old A2 til late 2014, and would hear it operating when the temp was low and the climate was not set to ECO.

Since having the 8, it's not been so cold, I've not heard anything or seen smoke from the underside of the front. Car heats up pretty damn quick compared to the old 1.4 3 cyl diesel I had. I replaced the thermostat and temp sensor on the 2, but the small CC diesel lump did not put out much heat. And the webasto would only work below a certain temperature. In theory this was good, but short journeys above that temp the engine wouldn't heat up and the webasto wouldn't function. Is it correct that on the 8 you have to set the climate to HI to have the webasto function, and be below a certain temperature?

John.