No Air coming out of heater....urgent help required.

**wali110** · 02-08-2009,07:48 PM

I am in urgent need of some help, if there is anyone in the west midlands and wants to earn some easy money by getting my blower motor to blow air again then please let me know.

I have taken it to a garage and done a diagnostic which said that the blower fan was faulty v2

Blower motor is fine however as I tested it and even tried a replacement, resistor is all fine aswell as the fuse.....

The problem started about a month ago.....it use to come on, stay on for around 5min then just shut down...then one day it never came on at all

There is nothing else i can think of guys.....please let me know if anyone knows anything about this sort of problem.....thanx guys

**SiliconS** · 02-08-2009,11:16 PM

Originally Posted by wali110

Blower motor is fine however as I tested it and even tried a replacement, resistor is all fine aswell as the fuse.....

How did you test it? (The fan on my A6 has stopped completely too.)

**wali110** · 23-08-2009,01:31 PM

still no luck guys.....its not the motor...not the fuse...not the resistor....a diagnostic says blower fan .......i dont know what else to do but sell the car before the winter comes :-(

**Peter D** · 23-08-2009,01:54 PM

This could be a faulty J126. This is the mosfet current controller for the fan. It too is mounted behind the glove box on part of the ducting. Regards Peter

**wali110** · 23-08-2009,06:37 PM

any idea what it looks like....what else could the problem be if not this one ?

**SiliconS** · 23-08-2009,10:46 PM

Originally Posted by Peter D

This could be a faulty J126. This is the mosfet current controller for the fan. It too is mounted behind the glove box on part of the ducting. Regards Peter

Thank you Peter. I Googled J126 and found this document:
http://www.vaglinks.com/Docs/Audi/C5...calTesting.pdf

I don't necessarily understand it but then it's Sunday night and I'm tired. Will read more tomorrow.

**SiliconS** · 04-09-2009,06:32 PM

Peter,
I found this part on eBay:
http://cgi.ebay.co.uk/ws/eBayISAPI.d...m=250378790432

I'm hoping this is the J126 controller that you mention. I've removed mine from the car and discovered that one of the three terminals has got hot enough to melt the insulation around two of the wires.

However, the bare wire also has some corrosion visible. Question is, which came first: the heat or the corrosion?

Is it worth replacing the black component or is the dodgy wire the cause rather than a symptom? The wire is part of the loom so that wouldn't be an easy thing to replace. I can cover it with heat-shrink sleeve to protect it if all I need is a new 4B0 820 521 thing. Is there any way to diagnose the 4B0 800 521 thing with a multimeter?

Would be grateful for any advice you can give.

**Peter D** · 04-09-2009,07:19 PM

The heat will have softened tthe press on connector so idelly they need to be replaced and ideally a new connector moulding as well. Ask Audi if they can suppy same. Regards Peter