Heater Blower

S8 TYW · #1 16th November 2011, 09:15 PM

Can anyone shed some light on this.

My Blower control has a mind of its own,
first thing in the morning it takes about 5-10mins for the blower
to activate, once on i have no control over the speed
of the blower, even if i turn the speed down on the mmi screen
it dosent change.

Anyone have any ideas? could this be a faulty resistor somewhere

Thanks

A8 Doc · #2 17th November 2011, 07:42 AM

Tricky one and i'll be honest do you have VAGCOM.

On most cars i've seen it's normally down to a faulty climate control unit. The lights change, but it doesn't send the correct signal.

Now the problem on here is the HVAC panel sits on the MOST network. And seems to be adjusting the MMI screen, therefore it is sending a signal..... in theory.

If it was me I would plug in VAGCOM and see if it shows the change via measuring blocks. This will tell you if it is truly sending the signal. If it is not, then replace HVAC.

I'm suspecting the heater motor though. I assume temperature is fine, just literally blower speed?

S8 TYW · #3 18th November 2011, 11:41 AM

Thanks for the reply.

Yes i do have vagcom, but havent really used it alot so how would i go about
seeing if these measuring blocks change?
i take it i would need to entry module 08 Auto HVAC
and then what?

Quote
(I'm suspecting the heater motor though. I assume temperature is fine, just literally blower speed?)

Yes the Temperature is fine, just the fans are the problem

Thanks

Godders · #4 18th November 2011, 02:40 PM

Quote:

Originally Posted by S8 TYW

Thanks for the reply.

Yes i do have vagcom, but havent really used it alot so how would i go about
seeing if these measuring blocks change?
i take it i would need to entry module 08 Auto HVAC
and then what?

Yes it is 08 Auto HVAC but you'll find there's no published label file

However I have produced one which will give you all the labels for the various measuring blocks

Drop me a PM if you want it and I'll give you instructions where to save it to and how to use it.

Without it you won't be able to diagnose or check anything in the HVAC module, there's just too much info in there which means nothing without a label file

Note to self, I must send it to Ross Tech for inclusion in a future release

S8 TYW · #5 18th November 2011, 07:09 PM

Many Thanks for that i will PM you

Cheers

Godders · #6 18th November 2011, 07:38 PM

Got your message and have PM'd you. We're only a stones throw from each other so it may be worth meeting up

A8 Doc · #7 21st November 2011, 07:18 PM

Glad you are getting sorted, agree you do need HVAC labels, I forgot they wern't on the D3.

If you meet up might be easier to swap HVAC panels and try that. It's very easy to do. Remove the ashtray and undo bolts IIRC... It's been a while/

S8 TYW · #8 22nd December 2011, 08:54 PM

Just a quick update on this......

Also like to thank bry for taking time to help in this problem,
hope you and your family have a good Xmas

OK after some trawling on the internet, and reading a few similar problems
regarding the fans having a mind of there own, i decided to change the blower module which is located next to the fans themself.
End result is all working perfect

Once again bry many thanks

Tony

Godders · #9 23rd December 2011, 09:14 PM

Tony,

It was a pleasure though frustrating we couldn't fix it and ultimately required the blower module replacing, not cheap as I've just found out.

Looks like I now have a similar problem

(must be catching), though I think mine is down to the fan so I'll be replacing that over the hols - it just arrived today.

Something else to add to the small claims claim

, that's going to be an interesting day !

Have a great Christmas and New Year too.