There is no airflow from any climate control vent unless Max A/C is selected. Is this typical of cabin heater failure?

[f1eng]

A couple of days ago I noticed the car was very stuffy and uncomfortable and noticed no flow through any of the climate control vents.
I tried going to the menu and selecting different modes and in the individual "moving" the flow direction but still no flow in any setting.
TBH I thought "maybe it will work again tomorrow" since I have little confidence in complex software driven car functions and sometimes switching off and leaving it means a fault goes away - I much prefer old, simple, light and reliable personally.
Anyway, it still doesn't work and makes the car a pretty unpleasant place to be.

I had a warning in the App about a cabin heater needing replacing so wondered if anybody had a similar fault when their cabin heater failed?

Yesterday in the rain the cabin started misting up so badly it was getting too poor visibility to drive safely and I tried Max A/C - then there was strong flow through the vents, so unless there is a specific max A/C fan it isn't a fan failure.
The demist selection cleared the lower half of the screen so I could see out.

Leaving windows open a bit makes it more tolerable but leaves a stream of water coming in if it is raining.

Anyway my main question to those who have had a cabin heater failure was it accompanied by no flow through vents or do I have an additional failure?

Sponsored

 

[W1NGE]

A couple of days ago I noticed the car was very stuffy and uncomfortable and noticed no flow through any of the climate control vents.
I tried going to the menu and selecting different modes and in the individual "moving" the flow direction but still no flow in any setting.
TBH I thought "maybe it will work again tomorrow" since I have little confidence in complex software driven car functions and sometimes switching off and leaving it means a fault goes away - I much prefer old, simple, light and reliable personally.
Anyway, it still doesn't work and makes the car a pretty unpleasant place to be.

I had a warning in the App about a cabin heater needing replacing so wondered if anybody had a similar fault when their cabin heater failed?

Yesterday in the rain the cabin started misting up so badly it was getting too poor visibility to drive safely and I tried Max A/C - then there was strong flow through the vents, so unless there is a specific max A/C fan it isn't a fan failure.
The demist selection cleared the lower half of the screen so I could see out.

Leaving windows open a bit makes it more tolerable but leaves a stream of water coming in if it is raining.

Anyway my main question to those who have had a cabin heater failure was it accompanied by no flow through vents or do I have an additional failure?

Hi Frank, I didn't lose flow but had no heat when it happened to me.

If the app has flagged it then there must be a recall for your car but unfortunately it does sound like it could be a failure either of the beater or elsewhere in the HVAC.

 

[f1eng]

Hi Frank, I didn't lose flow but had no heat when it happened to me.

If the app has flagged it then there must be a recall for your car but unfortunately it does sound like it could be a failure either of the beater or elsewhere in the HVAC.

Thanks Adrian.
The App flagged up that the software check found the cabin heater to be going to need replacing and I booked the car in for a service but not until October and a couple of long trips to do before that mean if this keeps up I won't be able to use it .

Probably a sensor or software failure since the fan does blow through the vents for max A/C.

 

[chun]

You could try a 2 fingers reset; that also resets all AC stuff.

A 12V disconnect might also help ; or maybe use the software from @prj and see if there’s any error from the AC, and you’ll know for sure

 

[prj]

Use my app to pull the codes, there's a ton of different flaps and my 12000km Taycan had a failure on two of them, which I had to fix before I got the approved warranty on the car.

 

[dcao]

Happened to me today. Frank, did that heater replacement fixed this issue?

 

[f1eng]

Happened to me today. Frank, did that heater replacement fixed this issue?

Not sure.
I tried a few different settings and the one that seemed to make it go away was initiating the cabin pre-heat from the phone app.
I think there had been some sort of glitch associated with an app update since the temperature in the app was in Fahrenheit which I haven't used for over 50 years! and after setting the preheat for 10 minutes the climate control seems to have gone back to normal before the heater matrix recall.

 

[dcao]

Thanks. Think during the hot weather the car's aircon will work and the heater may never get triggered but during the cold months the heater will start to expose themselves? In my case, a trunk open/close, a windscreen wash and aircon max will trigger airflow from the vents (for a few seconds on the trunk/windscreen wash). The car was dead cold and even the aircon max wouldn't really work during the morning time (Cabin temp too low maybe?)

 

[Midlifecrisis]

I had a heater failure - I am pretty sure that air still blew through the vents though. Just cold air - in December.
The only time I had something like you describe was when I first had a Taycan and there was very little air blowing. I thought there was a fault but the fan just wasn’t on auto, it was on a low speed. Could Auto fan speed have got turned off somehow and back on when you preheated your cabin?

 

[dcao]

Thanks Ian. In my case, the fans were working, at least they were blowing to somewhere. I can hear the fans blowing harder when fan speed was turned up higher but there's no air coming out of the vents when I put my hands over them. Some other guys had the similar issue which was discussed here https://rennlist.com/forums/taycan/1430193-ac-fan-issue-on-2020-taycan-turbo-s.html

 

[hifi239]

Maybe the Servo Motors? See this thread.

 

[dcao]

Yeah, thanks Will. I booked the dealer visit next month so will update by then. In the meantime, will have to borrow her XC90 a lot in this cold&damp Irish weather .

 

[f1eng]

Mine has gone back to no vent flow again today, both morning and afternoon.
Since the last time this happened the system has worked normally and the heater recall completed.
I needed maximum demist to keep the windscreen clear and had to wipe the other windows to see through. Like my first car, a 1960 Morris Minor.
What I hadn't noticed last time was that selecting the ventilation screen in the PCM showed the 3 choices but no flow graphics and whichever of the 3 I selected nothing changed and the normal steering circles didn't show.
Maybe because I had max demist on?
I will maybe try just switching off and on a few times to see if it is a PCM poor start up like just showing Porsche on the centre screen used to be, but I fear a visit to the dealer is inevitable.
I may even call Porsche assist and get them to tow it away it isn't nice/safe to drive the way it is

 

[dcao]

I got the fan/heating working by hitting the recirculation button today. It was so strange that recirculation button was like the opposite of what it is supposed to be. Something stranger was this, the mist was cleared by that button. The heater in passenger compartment was already changed in my car so the heater was ok after all.

 

[f1eng]

I got the fan/heating working by hitting the recirculation button today. It was so strange that recirculation button was like the opposite of what it is supposed to be. Something stranger was this, the mist was cleared by that button. The heater in passenger compartment was already changed in my car so the heater was ok after all.

I had tried that the first time it happened and I tried it again this time, nothing changed.
It seems to me it could be either a software or hardware problem but now I need to get it fixed.
Once was annoying, certainly more so than the PCM only booting as far as the Porsche screen but being normal at next use that has happened 2 or 3 times but not resetting for days and leaving the car all but impossible to see out of is not acceptable.
Luckily max demist cleared 90% of the windscreen otherwise I would have had to call the tow truck.

Sponsored