Heater control switch

00mike00 · 28-02-18, 09:11 AM

I’ll be replacing the heater matrix at some point in the near future, currently the heater control switch only works on setting 3 & 4, very occasionally setting 2 will work.
Would this mean a replacement switch or is it possible I could fix it?

urquattr085 · 28-02-18, 01:45 PM

Quote:

Originally Posted by 00mike00

I’ll be replacing the heater matrix at some point in the near future, currently the heater control switch only works on setting 3 & 4, very occasionally setting 2 will work.
Would this mean a replacement switch or is it possible I could fix it?

Hi Mike

If it's anything like the B2 setup, it could be the ballast resistor associated with the heater fan.

msh · 28-02-18, 03:20 PM

Yes, you can fix it. It is caused by heater switch contacts being oxydized or burnt. Contacts themselves could be removed from switches, just need to undo two bolts, and then tiny strips of sandpaper should be used to clean the contacts.

Ringmaster · 01-03-18, 02:22 PM

Got a similar problem with my C3. Replacing the ballast switch didn't solve it.

Airflow of setting 1 is hardly noticeable. 2 and 3 work as expected.

Tried sandpapering the area behind the selection lever but it made no difference.

Is there anywhere else I could sandpaper or check?

msh · 01-03-18, 09:47 PM

It's quite likely that the construction in question is similar to B3 one; contacts are behind heater switches, contact pack with six pin connector attached.

00mike00 · 07-03-18, 12:12 PM

Quote:

Originally Posted by msh

It's quite likely that the construction in question is similar to B3 one; contacts are behind heater switches, contact pack with six pin connector attached.

Thanks for the replies guys. I picked up the matrix yesterday so when I have a moment I’ll get behind there and sort it out.

28-02-18, 03:20 PM	#3
msh 4 ring whore! Join Date: Jun 2008 Location: Rucava, Latvija Posts: 3,816	Yes, you can fix it. It is caused by heater switch contacts being oxydized or burnt. Contacts themselves could be removed from switches, just need to undo two bolts, and then tiny strips of sandpaper should be used to clean the contacts.

01-03-18, 02:22 PM	#4
Ringmaster Senior Member Classic Audi Club Member Join Date: Apr 2008 Posts: 1,326	Got a similar problem with my C3. Replacing the ballast switch didn't solve it. Airflow of setting 1 is hardly noticeable. 2 and 3 work as expected. Tried sandpapering the area behind the selection lever but it made no difference. Is there anywhere else I could sandpaper or check?

01-03-18, 09:47 PM	#5
msh 4 ring whore! Join Date: Jun 2008 Location: Rucava, Latvija Posts: 3,816	It's quite likely that the construction in question is similar to B3 one; contacts are behind heater switches, contact pack with six pin connector attached.