Golf GT TDI MK7 No heat from vents

[vwsam_]

Hi all. Just reading through your posts so far. I have a 64 plate GTD on 70K. Recently, heating on the passenger side vents, including the footwell and the 2 above the centre console, work fine. However my driver's side and footwell vent blow cold. Used a mates VCDS to diagnose faults:

2 Faults Found:

1048834 - Functional Limitation due to Energy Management
B10CD 00 [009]

and

1048835 - Functionality limited due to Engine Control Module
P1719 00 [008]

Anyone clued up on if it's the matrix or not, and how much it would cost to fix? NB: silica bag was removed a couple years ago, so won't be that.

[Kleon524]

Hi - did you manage to resolve this issue? I have exactly the same symptoms although I’ve not checked for any codes as of yet - when I looked through the history of my car though, the previous owner already paid £1200 at a main dealer to have the heater matrix changed!

[Nemophilist]

Resurrecting this thread as my search of the same fault with my MK7.5 GTD has bought me here.

Last December I had my waterpump replaced and at the same time asked them to change the coolant tank with no silica bag as I had friends who had had their systems clogged up after the silica bag had split in theirs.

On the last few cold mornings I have realised my heaters are no longer blowing any heat at all.

I am about to book it in with my local specialist but wondering what it could be if its not a clogged matrix?

Edited to add - i have seen that in USA they have extended the warranty on the heater on MK7 models to 120k miles or 10 years but this doesnt seem to apply in the EU

Edited by Nemophilist on Tuesday 31st August 09:38

[Patch1875]

Matrix was certainly the issue with mine but I had the bag split happen.

[Nemophilist]

I just had a look under the bonnet and the coolant is below the min line.

I had to top it up just a few weeks ago.

No sign of where its going but the oil cap is clean.

I did hear a loud gurgling noise from behind the dash just 2 weeks ago which I am now thinking is connected

[winstonw]

Heater on Golf MK7 GTD stopped working and a local dealer diagnosed the silica bag problem.
VW customer service were of no help and refuse to acknowledge there is a design or manufacturing problem with the silica bag which sometimes ruptures.
After flushing the cooling system with clean water and removing the blocked heater matrix, water eventually flowed through the matrix in both directions, when connected to a garden hose.
Heater now working again although will probably not purchase another VAG vehicle due to VW customer service response on this issue.

[Nemophilist]

It does seem strange that VW US seem to acknowledge the issue and UK doesn't

To update what happened to my car - my local independent garage flushed through the hoses and the heating worked again. This only seemed to continue for a few weeks before it clogged again.

I have now replaced the matrix and I am back to full heat again. It wasn't as expensive as I thought. The garage only charged me 2 hours labour to replace it.

Considering VW charge £1200 to do the replacement, I was pleasantly surprised. As pleasant as that can be for something that shouldnt happen in the first place.

[Sheepshanks]

winstonw said:

.... will probably not purchase another VAG vehicle due to VW customer service response on this issue.

VW contract out customer service to some random call-centre and their sole purpose is to fob you off.

The dealer can apply for goodwill but they won't tell you as it's better for them if you pay.

Or you could have bought an extended warranty.

[Nemophilist]

I had mine flushed with new coolant initially, but it didn't work and had to have the heater matrix replaced in the end.

It cost about £350 from a local independent instead of the £1200 that VW wanted.

I had it done last year and its been running with nice hot blowers ever since.

Good luck with getting yours sorted.

[shxm.95]

shxm.95 said:

Hi all, I’ve recently purchased a Golf MK7 1.6TDI which has 69K miles on it. I’ve had the vehicle for 6 to 7 weeks. Over the last few weeks all of a sudden the car started blowing cold air even when the vents were turned to high heat. The car is still under warranty and I have gave it back to whom I purchased the vehicle from. Now they’ve changed the water pump, thermostat sensors they’ve had it flushed and added fresh coolant. They’ve also changed the cabin filter. The car runs warm when stood still or at low speeds, however as soon as I put my foot down to pick up speed it starts blowing out cold air?? It’s really becoming a pain in the back side as I’m paying for a car which hasn’t even been drove for the duration which I’ve had it. Can anyone please help me or give me any advice. It would be much appreciated. Thank you.

[shtu]

Silica bag in the header tank bursts, which blocks heater matrix.

Common as.