Volkswagen Passat Forum banner
Cancel
Create thread New Garage Forums

Need AC Advice

Tags
advice need
Jump to Latest
31K views 22 replies 7 participants last post by  TheAmazingDave  
T
#1 ·
My Passat has had an AC problem since I picked it up last month. Through the tips I've learned here, I was able to check the Climatronic codes and found error 313 which relates to outside air temp sensor.

So I got pissed off today that it wasn't working, as it has only worked maybe 8% of the time the last few weeks. I remembered how to access the diagnostic menu and all the temps looked good, except on diagnostic page 04, where the temperature displayed is -47 degrees Centigrade!

So, tell me if this sounds right. Even if I set it on full max cool, the compressor does not run. Is this because it thinks its below freezing outside, so it's just pumping in outside air? I'm thinking this is true since it will also switch from recirculate to outside air when it faults.

So again, will it cut the compressor if it thinks it's freezing outside, or do I have another problem along with this temp sensor?

Also, anyone know where the outside temp senor is? I think it may be in the HVAC intake ducting behind the glovebox, but don't know for certain.
 
T
#3 ·
Cool, thanks for the tip. Anyone else know if this problem will cause the compressor to not run since it thinks it's freezing outside?

Edit: also, thanks to kenblasko, I know that error 313 on the Climatronic is the Temperature Sensor in Fresh Air intake duct (G89), Open or Short to Plus. This is mounted down by the radiator?
 
T
#5 ·
Thanks again!

For anyone else with troubles, I just found a list of what each diagnostic "page" displays. Most of the lists you find are not exactly for US models it seems, but this looks right, as I can verify some of the displayed values correlate properly to the list, including vehicle speed which is properly listed as 16, not 17. :)

http://home.online.no/~b-bado/car/Climatronic.xls
 
0
#12 ·
The link generates a popup indicating a need to download officeopen.org which I've done!

1.However still unsuccessful.

BTW Is the air quality still being impacted with the No. Calif lighting fires?

2. Notice you've in software: My CPU had a software glitch and I restored it BUT in the process was NOT able to use previous Mozilla Firefox Bookmarks which were EXTENSIVE & since the new 3.0 version only allowed one to import from IE which I haven't used in 5 yrs. So I would love to know how I could bring to the present... my former Firefox bookmarkS!

TIA for 1&2 above

Anson
 
T
#7 ·
OK, I did more figuring. Page 4 shows the average outside temp from readings from the sensors G17 and G89 which are shown on pages 5 and 6, respectively.

G17 is labeled as the bumper sensor, and it reads correct and steady. G89 is usually pegged at -50 and will start reading erratically from -50 all the way up to the correct temp, and oscillate too rapidly to read on the display. Occasionally, it will hold at the correct temp long enough to bring page 4's average up, and sure enough, the compressor comes on.
 
T
#13 ·
Yea, the air has been pretty bad lately, but the last week has been decent here in San Jose. It's been a bad time for me to not have AC. :( Another problem is this strange howl I get when recirculate is on, another annoyance to track down.

Here's the contents from the Excell file, I've verified most of these on mine, the other lists that say vehicle speed is page 17 do not match up at all:

Channel Information
0
1 Temp climatronic instrument panel (-G56-)
2
3 Sunlight photo sensor (located on dashboard) - values from 0 - 120%
4 Outside air temp - -E87- Calculated from -G89- and -G17-
5 Outside air temp - -G17- lower bumper sensor
6 Outside air temp - -G89- air intake duct sensor
7 Outlet temp Floor sensor (-G192-)
8 Outlet temp Center sensor (-G191-)
9 Blower speed
10 Measured blower speed
11 Temperature regulation 0 = Hot, 255 = Cold
12 Dashboard ventilation valve
13 Recirculation valve
14 Lower ventilation valve
15
16 Car speed
17
18
19
20
21
22
23 Coolant temp in HVAC heater element (?)
24 Temp wanted in heater or car (?)
25 Position heated air
26 Actual value
27 Position cooled air
28 Position footwell/defrost
29 Actual value
30 Position instrument panel vents
31 Position resirc air passenger compartment
32 Actual value
33 Stop position fresh air passenger compartment
34 Position defroster
35 Actual value
36 Position footwell
37
38
39
40
 
G
#14 ·
Found this from Bentley:

15 - Outside Air Temperature Sensor G17
Function: Temperature sensor controls temperature flap and fresh air blower speed dependant of temperature measurement.
In event of sensor malfunction, Fresh Air Intake Duct Temperature Sensor G89 measurement value is used instead. If both sensors malfunction, operation continues with default value of 10 ° C (50 ° F). Air recirculation not possible. A/C Control Head E87 display indicates: "--"

And

"Replacing:
Remove glove compartment Body Interior - Repair Group 68
Reach behind heat/A/C unit from below.
Turn sensor 90 ° and pull out."
 
T
#15 ·
So even though the Climatronic was reporting the faulty sensor, it was still trying to use it to compute the outside temperature. This was bringing the calculated value for the outside temp down to extremes of -47 degrees centigrade. Through watching the sensor outputs, I noticed that the compressor will only run it seems over 10 C.

After disconnecting the sensor completely Climatronic finally decided to ignore the input and run off of the bumper sensor. The average outside temp slowly crawled back up and it now seems to be working fairly normally. Well, I haven't tried auto temperature regulation, I'm keeping it set on Low untill the new sensor comes in. :)
 
T
#16 ·
Just checking in after a few days. The system is now completely ignoring the mising sensor, and the average outside temp displayed on diagnostic page/channel 4 is now the same as the bumper sensor reading on page 5, and the Climatronic is operating properly again, albeit the temperature calculations may not be exact.

I ordered a new sensor from my local dealer and it should be here tomorrow.
 
T
#17 ·
Dave - Awesome thread you have here.

Got a question, im having a problem similar to your (my car is Manual AC controls though) Can I look at all the channels listed above with Manual AC Controls or is that only for the Cliamatronic cars? How exactly do i look at that stuff in vagcom? All i have really played with is engine suff.

Thanks!
Ethan
 
T
#18 ·
Hey Ethan, the "pages" I am referring to are part of the Climatronic's built-in diagnostic system. To be honest, I don't know if manual AC cars generate faults, or if there is a similar diagnostic system available with VAG-COM. I hope to be picking one up soon, I'm anxious to tweak around with it.
 
J
#19 ·
Been attentively reading this thread. My problem is just the opposite. Both sensors are ready way over 100C, in fact, the G89 goes over 200C often. I get codes on all the flap servos and as a result I get no heat. I just took apart the glove box and removed the G17 sensor and think I found the G89 sensor sitting in front of the A/C condensor way down at the bottom, accessible thru the lower vent grill. I assume it takes several start cycles to get the head unit to realize that it has no sensors and flip to default?
 
T
#22 ·
Jersey_joe said:
Been attentively reading this thread. My problem is just the opposite. Both sensors are ready way over 100C, in fact, the G89 goes over 200C often.
Click to expand...
That is a common misconception regarding the diagnostic display. There IS a decimal point. 10.0 and 20.0 would be expected readings. I highly doubt it would display a temperature above 100 degrees Centigrade. When G89 reads 10 degrees, what's the reading of G17?

I get codes on all the flap servos and as a result I get no heat. I just took apart the glove box and removed the G17 sensor and think I found the G89 sensor sitting in front of the A/C condensor way down at the bottom, accessible thru the lower vent grill. I assume it takes several start cycles to get the head unit to realize that it has no sensors and flip to default?
Click to expand...
G17 is behind the front bumper. G89 is under the pollen filter in the HVAC intake tract. The sensor you refer to near the condensor should be the G17sensor, unless you're mistaking the evaporator temp sensor (the part in the car) which I'm not sure of the code for. G17 (front bumper) and G89 (HVAC intake) are the only sensors used to determine outside air temperature.
 
T
#23 ·
In case you and Jersey Joe didn't notice, this thread is dealing with air conditioning malfunction. Climatronic doesn't care what the temperature is outside, if you want heat, it will supply it. If your heater is cranked and no heat is output, you likely have a plugged heater core.
 
Volkswagen Passat Forum
posts
3M
members
167K
Since
2002
Passatworld is a forum community dedicated to Volkswagen Passat owners and enthusiasts. Come join the discussion about mods, Quattro, Turbo Diesel, reviews and more!
Full Forum Listing
Explore Our Forums
Volkswagen Passat B5 Discussion B5 Garage Anything Auto New Member Introductions Wheel and Tire Forum