LarryJa

I got a whff of engine coolant in my cabin. Then, all the hvac, including seat heat, rear defrost & hvac controls and displays, lost power.
VCDS tells me that the climatronic control module has lost power (what a surprise?!).
I suspect that the module is fuse protected. I, also, suspect that the fuse for it would be in the electrical panel,up front, on the drivers side of the cowl area.
Neither the owners manual nor my ELSA repair manual provide information on the fuses in that panel.
Does anyone here know whether or not the hvac module is fuse protected &, if so, in which panel & position is that fuse located.
As I originally stated, I must find out why I smelled a whiff of coolant first. Hopefully, I don't have a coolant leak that fried the hvac controls module....

raj99

Larry, take a look at this...it may help

LarryJa

Thank you Raj!

LarryJa

I replaced the blown 10A fuse for the ac controls &, now, climate system is working. However, I still have an occasional strange odor coming out of the system.
More investigation is necessary.....
Also, I have not yet changed the cabin charcoal filters. That may be a good place to start..?

LarryJa

I changed that cabin air filters. I don't think that they have ever been changed before! Very blocked! Probably the cause of my odors!
we'll see...

LarryJa

I, also, found out that my passenger side dash vent was always pumping out hot air again.
I guess it's time to clean the solenoids in the heater control valve again...I think I'll put in some new screws for the solenoid caps this time. One of the torx heads broke off last time, putting them back in. New screws with more substantial heads are a cheap remedy. I think that I can get a fine drill bit into the control valve base, to replace that broken screw this time.

LarryJa

Well, I had the time today to check out my heater control valve.
It turns out that the passenger side solenoid coil was shorting out. That's what caused the initial fuse to blow.
Today, I took the control valve solenoid covers off, & it was obvious that there was a problem on the passenger side. The inside of that solenoid cover had a sticky, cruddy "gunk" coating & the area at the back of the coil's base had the same "crud". I believe it to be the winding insulation from inside the coil. I believe that the initial cause of my issue was the solenoid coil shorting out, causing it to heat up & melt the insulation, allowing a further shorting of the coil, until the fuse blew. After that, the passenger coil lost continuity, which allowed me to replace the fuse & regain most cabin HVAC functions, except that the passenger side was always pumping out HOT air.
This morning, after cleaning up all the "gunk", I reassembled the heater control valve & started the car. I immediately saw the passenger side solenoid "smoke" & the fuse blew.
I've ordered a used replacement control valve off of eBay. It'll be here by Saturday.
In the interim, I've disconnected the power supply from the control valve. That gives me most cabin HVAC functions & constant medium heat flow.
If the used replacement valve is identical in construction to my present one, I may just use the electrical portion of the replacement on my existing valve body. That way, I won't have to pull the coolant & heater hoses off. That would save a ton of time & aggravation, working in that tight cowl area.
We'll see.

Rodney9999

Hi Raj can you help same issue here do you have any information on the A4 fuse locations for the climate controls and windows?