VAG-COM

Control Module Part Number: 8D0 820 043 P
Component and/or Version: A4 KLIMAAUTOMAT D58
Software Coding: 00140
Work Shop Code: WSC 63351
1 Fault Found:
00787 - Temperature Sensor in Fresh Air intake duct (G89)
30-00 - Open or Short to B+


My HVAC controls won't respond at random times. Could this be the cause of my HVAC controls, functioning and not functioning intermittently?


Audi B5 S4 2.7T Climate Control Electrical Sensors ES#362495 Temperature Sensor - 4A0820539A This is the sensor that vag-com, says is faulty.


Could anyone tell me if they have replaced this pesky, sensor? Also, the HVAC controls, when they don't function or respond to my presses, feel like they are stuck.

like there is something sticky like soda that spills onto the controls, like so many B5 and S4 owners have done.

The thing is, the buttons acting like they are sticking, has nothing to do with any dried soft drink.

Its malfunction of the HVAC controls, causes the buttons to stick like that, so they don't pop out, once your finger is lifted from the buttons.

The only buttons that don't stick in is the circulation arrow button and the rear window defog buttons, they push back out, if i let them go.

I know a lot of people have misdiagnosed this issue as some soft drink, being spilled over the HVAC controls and i am here to tell everyone that this malfunction is a issue of itself and not anything spilled.

Case and point, when the HVAC controls, decide they want to work, the buttons function freely and perfect without any kind of "sticking in". so i know it has to do with a malfunction.

I'm going to order this sensor from here, being its cheaper here, opposed to ecstuning, where they over charge for OEM Audi parts, where as genuinevwaudiparts.com sells their OEM parts at a discount.

2001 Audi A4 Quattro Parts - genuinevwaudiparts.com

Its #19 in the diagram and 19 in the list all the way down the bottom of the list.


There are no other code in the HVAC 08 Bank, so it has to be, what is causing my HVAC controls to not respond, when i press them. and also cause the HVAC system to function and not function at random times.

Also, if i leave the controls alone with the heat on, it will stay on fine and won't turn off, even if the controls don't respond but the same happens if the HVAC is off and the controls don't respond, i can't turn it on ( it turns on fine but it won't function, meaning the whole HVAC controls are lite up but i can't operate them )

The car seems to remember the last setting the HVAC was on and continues, where it left off, when i come back and turn on the car at another time or the next day, it will either stay on and i can't turn it off or it won't turn on, because before i turned off the car, the HVAC system was working fine, so i turned it off, manually. But for whatever reason, sometimes it won't respond and i have to keep pressing the button, randomly while I'm driving and wait for it to kick in....


Thanks fellas, in advance.

 

ECS has that sensor for $14. Searched the part number and got this. I have replaced that sensor. It's really not that bad. You need to remove the black plastic panel that is above the passenger's feet. Then if you lay on your back and look up by the firewall, you will see it. It's a little tight but you can get your arm up in there and reach it.

 

I was thinking this write up is way easier than going through the glove box as you suggested? https://www.audiforums.com/forum/b5-...cement-200537/

Also, nobody has chimed in on if this is the actual culprit of my HVAC issue. Do you know if this is the problem and replacing this sensor would remedy my issue?

Yeah, i saw that aftermarket sensor but i figured, i might as well pull the trigger on the OEM one, being its a rather, inexpensive part, i might as well pony up and buy the better quality OEM sensor and save myself the trouble of facing this problem again in the near future. That after market might be 15.00 less than the OEM version but who knows how long it will last?

 

I don't know if it will fix your problem. I bought the $14 sensor and installed it about 2 years ago and haven't had any problems. The manual says to replace it in a way similar to what I said. You could do it the way it is done in that link, but I personally wouldn't. I know it looks easy, but there's really not enough room to get the sensor out that way which is why breaking the old sensor makes it easier and it can't be good to be pulling it out by the wiring harness.

 

Do you have a write up how to access the sensor, through the glove box? Do i have to remove the glove box or just let it hang off the hinges?

 

I ordered the Temperature Sensor in Fresh Air intake duct (G89) for Audina!

I ordered the aftermarket sensor as it was much cheaper:


966-914-926 Feb 7 2014 Feb 7 2014 Shipped

Sub Total: $13.97
Shipping - (USPS - Priority Mail): $7.51
Total: $21.48


Home Page ES#2500956 Temperature Sensor - 4A0820539

 

When I did it, I know I had a write-up someone had done but I haven't been able to find it again since. The best I could do is a page in german. I used google to translate the page to english so it's not perfect but you can find it here. I don't know what year A4 they were doing it on but removing the glovebox should be at least similar to what they did. I couldn't find a good write-up for removing the glovebox either. But I found a youtube video on replacing the heater core where they talk about removing the glovebox . Also, you don't have to remove the blower motor. The sensor has to turn 90 degrees to be removed. If you can't turn it from below, you can get at it to turn it from the top side.

 

Thank you much, jeckel20003. I'll give that link a try after i translate it.

I'll take a peek at that YouTube video as well.

 

I replaced my Fresh Air intake duct Temperature Sensor, today!

It was easy, going under the cabin air filter, than going through the glove box.

It took me about an hour, total to replace and put everything back together.

The only thing i had to do is break off a couple of pieces of plastic, near the lip of the hole, where i had to pull the sensor up, in between the metal and plastic gap.

Once i got the sensor out of the tiny hole it sticks out from, it fell down, So i had to break the plastic, so i could see down in the hole, so i can then fish it out, use a screw driver to wedge between the plastic and metal and pulled it out with a needle nose pliers.

Now all i need to do is clear the code with my vag-com, connected to my laptop, then the code shouldn't come back.

 

That's why I suggested not doing it that way.