Audizine - An Automotive Enthusiast Community

Results 1 to 26 of 26
  1. #1
    Established Member Two Rings
    Join Date
    Jul 17 2009
    AZ Member #
    45120
    Location
    Philadelphia PA & Pikeville KY

    2004 Audi A4 HVAC ECON light always on... advice...

    Guest-only advertisement. Register or Log In now!
    Hello Folks,

    Just need a quick opinion from the more Audi knowledgeable. About 4 days ago my 2004 A4 HVAC ECON mode light came on and will not shut off. Some mornings when I start out its off... but as I drive it switches over automatically.

    I DID A SEARCH FIRST... didnt come up with an exact match for my issue so this is why I'm asking. Also, the manual is no where to be found so please no one tell me to look at the manual...

    Any way... I am trying to narrow down the cause before I pay money to a mechanic... so my thoughts are 1) Low R-134a, 2) Fuse, 3) relay... Which seems most likely before I spend time or money...

    Many thanks in advance.
    Martin.

  2. #2
    Active Member Two Rings P-Lo's Avatar
    Join Date
    Jan 27 2009
    AZ Member #
    37962
    My Garage
    04 A4, MT
    Location
    Toronto

    low pressure on the refrigerant... you have a leak. I had this problem over the summer, not too bad a fix. find the leak, fix it, re-pressurize

  3. #3
    Veteran Member Four Rings BCsniper's Avatar
    Join Date
    Jan 29 2010
    AZ Member #
    54160
    My Garage
    B6 S4 6MT Avant, B6 3.0 Avant 6MT (for sale), C5 A6 2.8
    Location
    north ga
    Items for Sale

    look around for someone in the Philly area that has a Vag-Com and can check what codes you have

    I got lucky when it happened to me that I just had the hi-pressure switch go bad.
    The most likely scenario is you have a leak somewhere like P-Lo described or your AC compressor is likely on its way out



    .....but yes this topic is scattered all over AZ and other various sites, I'm not sure how you couldn't find it
    Last edited by BCsniper; 03-03-2011 at 10:54 AM.

  4. #4
    Established Member Two Rings
    Join Date
    Jul 17 2009
    AZ Member #
    45120
    Location
    Philadelphia PA & Pikeville KY

    Guys, Thanks for the replies... One more thing: Last night while at the bank drive through I began to hear this strange rattle very faint from the driver's side of the car that didnt change when I turned on the A/C system but increased in amplitude from idle to 1100 rpm before disappearing when I stepped on the gas. I am pretty sure the A/C compressor is on the drivers side front corner... Could the compressor have suddenly gone bad? Or if I am right and this NEW noise is from the compressor could it just be that the system is low on refrigerant and lubricant?

  5. #5
    Senior Member Two Rings
    Join Date
    Jul 21 2008
    AZ Member #
    31111
    My Garage
    2004 A4 1.8TQ Tip
    Location
    Auburn, NY

    I have had this problem for a while too but haven't dealt with it yet since its cold in upstate ny right now. From my research you should buy a bottle of r134a with stop leak but make sure to get the one with the pressure gauge right on it. Follow the directions to refill the refrigerant and if it is under normal pressure then you have a leak but if its at some crazy high pressure then the AC high pressure switch is bad. Speaking of this does anyone have the part number for the switch and the best as in cheapest place to buy it?

  6. #6
    Veteran Member Three Rings achilleas101's Avatar
    Join Date
    Mar 09 2010
    AZ Member #
    55787
    My Garage
    2006 Subie Legacy 2.5
    Location
    Falls Church, VA

    you heard a rattle? like a belt loose or something loose in the engine compartment? Did you at any point hear a kind of crunching sound (if you had the stereo on loud you may never have heard it) at any point? If so, the AC compressor is shot. I've had 3 of them go on me. The first one failed on first use. the 2nd one died 7 years later with a bit of a warning- it started making some odd sounds when it would engage, and then one day while driving i heard a crunch, and then some fluttering/rattling sound in the engine compartment that sounds like stuff getting tossed around a belt or something.

    Not saying this is what happened to you necessarily, but it is quite possible.

  7. #7
    Established Member Two Rings VIPdesigns's Avatar
    Join Date
    Mar 30 2010
    AZ Member #
    56856
    My Garage
    2006 Yamaha R1 AE
    Location
    Western, MA

    Quote Originally Posted by chuckA84 View Post
    I have had this problem for a while too but haven't dealt with it yet since its cold in upstate ny right now. From my research you should buy a bottle of r134a with stop leak but make sure to get the one with the pressure gauge right on it. Follow the directions to refill the refrigerant and if it is under normal pressure then you have a leak but if its at some crazy high pressure then the AC high pressure switch is bad. Speaking of this does anyone have the part number for the switch and the best as in cheapest place to buy it?
    I have a similar question.

    What should be replaced if you receive this code? 00819 - High Pressure Sensor (G65)

  8. #8
    Established Member Two Rings
    Join Date
    Apr 10 2011
    AZ Member #
    73745
    Location
    People's Republic of NJ

    Quote Originally Posted by VIPdesigns View Post
    I have a similar question.

    What should be replaced if you receive this code? 00819 - High Pressure Sensor (G65)
    I'm going to go out on a limb here and say that you might want to replace the high pressure sensor. :P After confirming that it's actually plugged in (sometimes the connector can lose contact or fall off), just buy a new one and have it replaced.

    http://www.ecstuning.com/Audi-B6_A4-...ioning/ES3518/
    2002 A4 1.8TQM
    Formerly...2001 A6 2.7TQM 6sp
    Before that...1999 A4 1.8TQM w/lots o mods

  9. #9
    Veteran Member Four Rings diagnosticator's Avatar
    Join Date
    Aug 26 2005
    AZ Member #
    7741
    Location
    Seattle, WA

    Quote Originally Posted by VIPdesigns View Post
    I have a similar question.

    What should be replaced if you receive this code? 00819 - High Pressure Sensor (G65)

    From Ross-Tech Wiki:

    "00819 - High Pressure Sensor (G65): Signal too Low

    Possible Symptoms

    Climate Control stuck in ECON Mode

    Possible Causes

    Insufficient Refrigerant Pressure
    Wiring/Connectors from/to High Pressure Sensor (G65) faulty
    High Pressure Sensor (G65) faulty

    Possible Solutions

    Check Refrigerant Pressure
    Check Measuring Value Blocks (MVB)
    Check Wiring/Connectors from/to High Pressure Sensor (G65)
    Check High Pressure Sensor (G65)".

    Only if the G65 refrigerant pressure sensor is faulty, replace the sensor.
    Vorsprung durch Technik

  10. #10
    Established Member Two Rings Allhailpoptart's Avatar
    Join Date
    Mar 16 2010
    AZ Member #
    56187
    Location
    NH

    Quote Originally Posted by Ritz View Post
    I'm going to go out on a limb here and say that you might want to replace the high pressure sensor. :P After confirming that it's actually plugged in (sometimes the connector can lose contact or fall off), just buy a new one and have it replaced.

    http://www.ecstuning.com/Audi-B6_A4-...ioning/ES3518/
    If you end up going this route you do NOT have to drain the AC system to change this sensor. Just unscrew the old one and screw the new one in. There is a one way valve depressed by the sensor once it's plugged in to allow the pressure to be measured. Once you take the sensor out nothing should come with it. Took <5 mins to change once you get the headlight out of the way. Just be careful not to overtighten it as it mounts into aluminum pipe.
    1995 URS6 Avant | 2.6L Eurospec Sport stroker motor w/lots of go fast goodies. | Tuned by Minhea Cotet @ MRC Tuning

  11. #11
    Established Member Two Rings VIPdesigns's Avatar
    Join Date
    Mar 30 2010
    AZ Member #
    56856
    My Garage
    2006 Yamaha R1 AE
    Location
    Western, MA

    Quote Originally Posted by Allhailpoptart View Post
    If you end up going this route you do NOT have to drain the AC system to change this sensor. Just unscrew the old one and screw the new one in. There is a one way valve depressed by the sensor once it's plugged in to allow the pressure to be measured. Once you take the sensor out nothing should come with it. Took <5 mins to change once you get the headlight out of the way. Just be careful not to overtighten it as it mounts into aluminum pipe.
    Thanks, Where exactly is this switch located? Which headlight should I remove? (Driver or Passenger side)

    Thanks again for the info and help.

  12. #12
    Senior Member Three Rings mwbunns4's Avatar
    Join Date
    Feb 20 2008
    AZ Member #
    25490
    My Garage
    2011 Audi S4 6MT, Audi A3 TDI
    Location
    Savannah, GA

    Quote Originally Posted by VIPdesigns View Post
    Thanks, Where exactly is this switch located? Which headlight should I remove? (Driver or Passenger side)

    Thanks again for the info and help.
    you will need to remove the drivers side headlight. once you do this, the AC condenser "shroud" will kind of be in the way. I just removed the top torx screw on it and was able to pull it out of the way enough to get to the sensor. I just replaced mine a month ago after going through all the same problems. AC works fine now, after filling it back up. Just make sure to take off the o ring and reuse it, unless it is somehow damaged.
    2011 S4 6MT Brilliant Red Titanium, Nav, ADS
    2013 VW GTI 6MT Drivers Edition

  13. #13
    Senior Member Three Rings mwbunns4's Avatar
    Join Date
    Feb 20 2008
    AZ Member #
    25490
    My Garage
    2011 Audi S4 6MT, Audi A3 TDI
    Location
    Savannah, GA

    Quote Originally Posted by VIPdesigns View Post
    Thanks, Where exactly is this switch located? Which headlight should I remove? (Driver or Passenger side)

    Thanks again for the info and help.
    Also, you will see the switch once the headlight is removed. it is attached to the condenser. Cant miss it.
    2011 S4 6MT Brilliant Red Titanium, Nav, ADS
    2013 VW GTI 6MT Drivers Edition

  14. #14
    Established Member Two Rings Allhailpoptart's Avatar
    Join Date
    Mar 16 2010
    AZ Member #
    56187
    Location
    NH

    Quote Originally Posted by mwbunns4 View Post
    you will need to remove the drivers side headlight. once you do this, the AC condenser "shroud" will kind of be in the way. I just removed the top torx screw on it and was able to pull it out of the way enough to get to the sensor. I just replaced mine a month ago after going through all the same problems. AC works fine now, after filling it back up. Just make sure to take off the o ring and reuse it, unless it is somehow damaged.
    Quote Originally Posted by mwbunns4 View Post
    Also, you will see the switch once the headlight is removed. it is attached to the condenser. Cant miss it.
    ^ These are spot on.

    I found a great picture of it on a4mods.com In this picture it's straight to the left of the red circle. Granted yours won't be missing a front bumper but..you get the idea.
    1995 URS6 Avant | 2.6L Eurospec Sport stroker motor w/lots of go fast goodies. | Tuned by Minhea Cotet @ MRC Tuning

  15. #15
    Established Member Two Rings
    Join Date
    Jan 18 2005
    AZ Member #
    4899
    Location
    Miami

    I had the same error, with 2 more. It ended up being the compressor (and the sensors were fine). It's a DIY if you can use a wrench and have about 8 hours. Apart from the regular tools, you just need a A/C vacuum, which they sell at harbor freight.

    First though, check with a can of refridgerant, in the low port. This is the one that is closer to the driver side of the car (there are two), under the plastic cover near the passenger door. Unscrew the nipple, hook it up, turn your A/C on high, see if you can disengage econ. A normal reading when the compressor is off is around 180~. When the compressor is on, it's around 30~. I was actually able to remove the accessory belt (after taking off the bumper) and work from there. My pulley on my compressor was essentially free spinning, as the core self-destructed and blew out the plate on the pulley.
    1* __

  16. #16
    Established Member Two Rings VIPdesigns's Avatar
    Join Date
    Mar 30 2010
    AZ Member #
    56856
    My Garage
    2006 Yamaha R1 AE
    Location
    Western, MA

    Quote Originally Posted by Allhailpoptart View Post
    ^ These are spot on.

    I found a great picture of it on a4mods.com In this picture it's straight to the left of the red circle. Granted yours won't be missing a front bumper but..you get the idea.

    Thanks for all the info guys!

    So I pulled the one pictured above ^^^ but it looks nothing like the one from the esc tuning website .

    I know i have refrigerant I checked it with a gauge on the low port. And the High port line gets really cold. I just dont get any cold air inside the car.

    I should say, that I was getting the econ light all the time until I ran VAGcom and it had the "00819 - High Pressure Sensor (G65): Signal too Low" code, I cleared it and the Econ light now goes off, but still no cold air.

  17. #17
    Senior Member Three Rings mwbunns4's Avatar
    Join Date
    Feb 20 2008
    AZ Member #
    25490
    My Garage
    2011 Audi S4 6MT, Audi A3 TDI
    Location
    Savannah, GA

    Quote Originally Posted by VIPdesigns View Post
    Thanks for all the info guys!

    So I pulled the one pictured above ^^^ but it looks nothing like the one from the esc tuning website .

    I know i have refrigerant I checked it with a gauge on the low port. And the High port line gets really cold. I just dont get any cold air inside the car.

    I should say, that I was getting the econ light all the time until I ran VAGcom and it had the "00819 - High Pressure Sensor (G65): Signal too Low" code, I cleared it and the Econ light now goes off, but still no cold air.
    thats not the one. Here is the sensor you need: http://www.ecstuning.com/Search/8E0959126C/ES441154/
    This is the exact one i used to replace my old one and presto, A/C works.
    2011 S4 6MT Brilliant Red Titanium, Nav, ADS
    2013 VW GTI 6MT Drivers Edition

  18. #18
    Established Member Two Rings VIPdesigns's Avatar
    Join Date
    Mar 30 2010
    AZ Member #
    56856
    My Garage
    2006 Yamaha R1 AE
    Location
    Western, MA

    Quote Originally Posted by mwbunns4 View Post
    thats not the one.
    This is the exact one i used to replace my old one and presto, A/C works.
    That one looks more like it, Thanks for your time. I will be ordering that this week.

  19. #19
    Senior Member Three Rings mwbunns4's Avatar
    Join Date
    Feb 20 2008
    AZ Member #
    25490
    My Garage
    2011 Audi S4 6MT, Audi A3 TDI
    Location
    Savannah, GA

    No problem man, good luck.
    2011 S4 6MT Brilliant Red Titanium, Nav, ADS
    2013 VW GTI 6MT Drivers Edition

  20. #20
    Established Member Two Rings VIPdesigns's Avatar
    Join Date
    Mar 30 2010
    AZ Member #
    56856
    My Garage
    2006 Yamaha R1 AE
    Location
    Western, MA

    http://www.koperformance.com/catalog...-Pressure.html

    Anyone ever order from KO Performance?

  21. #21
    Veteran Member Four Rings BCsniper's Avatar
    Join Date
    Jan 29 2010
    AZ Member #
    54160
    My Garage
    B6 S4 6MT Avant, B6 3.0 Avant 6MT (for sale), C5 A6 2.8
    Location
    north ga
    Items for Sale

    ^^
    No, but if you're looking to save a couple extra bucks than buying it from ECS, then just order it from GenuineAudiParts.com. The price is $50 over there, although keep in mind it'll take a few more days to get to you since it's coming from GAP's warehouse in CA, compared to coming from Ohio if you buy from ECS

  22. #22
    Established Member Two Rings VIPdesigns's Avatar
    Join Date
    Mar 30 2010
    AZ Member #
    56856
    My Garage
    2006 Yamaha R1 AE
    Location
    Western, MA

    Quote Originally Posted by BCsniper View Post
    ^^
    No, but if you're looking to save a couple extra bucks than buying it from ECS, then just order it from GenuineAudiParts.com. The price is $50 over there, although keep in mind it'll take a few more days to get to you since it's coming from GAP's warehouse in CA, compared to coming from Ohio if you buy from ECS
    Thanks for the tip!

  23. #23
    Established Member Two Rings
    Join Date
    Mar 05 2009
    AZ Member #
    39484
    Location
    oakland, CA

    I had a low AC charge on my A4. Basically, the AC would run, but it wouldn't get very cold... just a bit. Summer highs here in NorCal 925 area can hit 105 for a few days in a row, so naturally this was a big drag for me.

    I say some posts on home charging the AC. I figured for $40 I would give it a try. Stealership wanted $400 just to diagnose the issue and find the leak. Naturally, they were going to push me to buy a new compressor... installed for $1500, no doubt.

    I have found that just about all my VWs have seeped out a bit of R134 as they run over the years. My VR6 Jetta would need a recharge every 3 or 4 years. I always took it to a shop to have them do it for like $100 a visit.

    I used one of those blue cans of refrigerant with a gauge on it for $40 from Pep Boys. Worked like a charm. But I found that even if you followed the instructions, it was easy to overcharge the AC. The instructions say to start the car, crank the AC and wait 10 minutes before taking a gauge reading.... before deciding to inject more refrigerant. I did this, and I still crazy overcharged my AC. After charging, I drove the car for about 15 minutes with super cold air blasting me in the face (on a 100F day, no less)... things were good, until.... it cut off. I found you actually have to drive the car around for 20 minutes or so with the AC blasting to get an accurate reading on the gauge, then charge to spec, drive some more, repeat. I bled some of the refrigerant off, back to spec, and now it blow cold and does not cut off.

    Point is, the $40 Pep Boys can (with gauge) works great for a homebrew hack. It isn't a real repair, but I personally don't have $1500 to drop on a new compressor. If I have to goose it every few years (or even once a year), I can live with that.

    I would suggest trying that if the new pressure sensor doesn't fix the issue.

    I have heard that the stop leak refrigerant will just gum up other components. I would steer clear.

  24. #24
    Senior Member Two Rings B6_Dolphin's Avatar
    Join Date
    Apr 10 2005
    AZ Member #
    6059
    My Garage
    2008 RS4 Cabriolet - Misano Red/Silver; 2015 Allroad Premium Plus - Brilliant Black/Titanium
    Location
    Mukilteo, WA
    Items for Sale

    With regards to the A/C recharge, the dealer in this case, may be the best approach. Why? They have the special machine that totally evacuates the charge (including the oil), and then introduces the R-134 and the correct amount of compressor oil, all in one step (watched it in action myself). It takes no more than 15 minutes to complete.
    2003 A4 1.8TQ - GIAC K04 Flash, Borg-Warner K04-15, ER Sport FMIC (Black Anodized) , Fast Intentions 300 CPI HFC & D/P, Forge 007 DV, Fluidampr Harmonic Dampener, KW2 C/Os, 18" Matte Black miro 111's, S4 Rear Stab, 2.0 FSI Coils, Euro Matte Black Upper & Lower Grills, Dieselgeek Panzer Plate
    2008 RS4 Cabriolet - EPL Tune, Apikol Rear Diff Mount, VentureShield full hood/front clip/rockers/rear qtrs, R8-style Oil & Coolant Caps

  25. #25
    Registered Member One Ring
    Join Date
    Dec 05 2011
    AZ Member #
    84839
    Location
    philippines

    Is it normal to have condendensation on copper freon pipe line connected to ouside condenser unit(HVAC)?? If not then what should be done to prevent condensation?? Even though the copper pipe freon line(cold line) is already insulated....please let me know, what to do??....
    Thanks,
    Jared from Savannah, Ga
    www.aactionair.net

  26. #26
    Veteran Member Four Rings diagnosticator's Avatar
    Join Date
    Aug 26 2005
    AZ Member #
    7741
    Location
    Seattle, WA

    Is the condensation between the compressor and the condenser? No that is not normal. That is a sign that the system is overcharged. That length of tubing should be hot with the system in operation.
    Vorsprung durch Technik



Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  


    © 2001-2014 Audizine, Audizine.com, and Driverzines.com
    Audizine is an independently owned and operated automotive enthusiast community and news website.
    Audi and the Audi logo(s) are copyright/trademark Audi AG. Audizine is not endorsed by or affiliated with Audi AG.