Climatronic problems-heat stuck on

6456 Views 8 Replies 4 Participants Last post by Tomvw, Apr 16, 2022

Xplorer

Discussion Starter · Sep 23, 2017

During a 12hr road trip yesterday the Passat decided that rather than supplying a/c thru the dash vents, that heat would be a better idea. Wouldn't be bad, but it was 85+ degrees outside to begin with. With the system shut off it still made the closed dash vents almost too hot to touch. It seemed as even with the system in the off position , it had the heater flap open and the recir flap open. Searched the site this morning and looked for answers. Found a thread that described how to access the fault codes by holding the recir and econ buttons with the key in the on position. The display remained the same other than turning the recir and econ on and off as I tried several times to get codes. Note: the system was working properly and supplying plenty of cold air then just went into this undesirable mode. While stopped for lunch on the trip, I disconnected and reconnected the neg. battery cable and waited a half minute or so before reconnecting it. Nothing changed. Thanks for reading the wall of text.

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FrescoGreen01.5

· #2 · Sep 23, 2017

You have to hold the buttons with the key off, then keep holding them while you turn the key on. That will get the Climatronic in to diagnostic mode.

There are four electrically operated dampers. Odds are, you'll get a code for one (the temperature damper) or all four. Post all the codes you get.

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Xplorer

Discussion Starter · #3 · Sep 23, 2017

That got me into diagnostics, thanks. left side of the display 1st showed 4F7, then 4F8, 4FA, 513, and then finally a 318 as I scrolled thru. Does this help?

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FrescoGreen01.5

· #4 · Sep 23, 2017

You need the full Climatronic self-diagnostic write-up. I sent you a link in a private message.

You've got codes for three of the four flaps (dampers, servos). That most likely indicate an issue with the flaps; trouble with all four often indicates an issue with the Climatronic head unit. (There's a 5 volt, 10 mA, power supply that's used to read the servos positions. If it fails, the head unit doesn't know where any of the servos are located.)

But first things first: I'd suggest you clear the codes, then rerun the test. That will often resolve all but one or two of the codes.

FYI, the servos, one per flap, consist of a 12 VDC motor and a potentiometer for position feedback. All 5 wires run to the head unit. It applies 12 volts DC to the motor in the appropriate polarity to move the flap in the necessary direction. The potentiometer has 5 volts on one end, 0 volts on the other, thus the voltage on the wiper is proportional to the position.

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Xplorer

Discussion Starter · #5 · Sep 24, 2017

Thanks for the link. I re-accessed the codes and found only the 4FA before getting the 000. I reset the system and started to look at other things. I put it up on the ramps so I could get a better look at the compressor clutch (didn't get that far). I noticed that the electric fan for when the A/C in on was working, but noticed the main fan barely turning. As it idled it did pick up speed, but almost looked like I could just stick a finger in there and stop it (I'm not that stupid to try that though lol). Since it's already mid 80's and getting hotter, I figured I'd post what I found so far. I will continue tomorrow morning before it get stinking hot out again.

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punkass912

· #6 · Apr 13, 2022

Xplorer said:
Thanks for the link. I re-accessed the codes and found only the 4FA before getting the 000. I reset the system and started to look at other things. I put it up on the ramps so I could get a better look at the compressor clutch (didn't get that far). I noticed that the electric fan for when the A/C in on was working, but noticed the main fan barely turning. As it idled it did pick up speed, but almost looked like I could just stick a finger in there and stop it (I'm not that stupid to try that though lol). Since it's already mid 80's and getting hotter, I figured I'd post what I found so far. I will continue tomorrow morning before it get stinking hot out again.

Did you by chance get this issue fixed? Currently dealing with this sort of thing.

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Tomvw

· #7 · Apr 14, 2022

See this self diagnostic test. (Read second paragraph before using)

http://www.saunalahti.fi/~jues/Climatronic_Self_Diagnostics.pdf

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punkass912

· #8 · Apr 14, 2022

Tomvw said:
See this self diagnostic test. (Read second paragraph before using)

http://www.saunalahti.fi/~jues/Climatronic_Self_Diagnostics.pdf

I very much appreciate your reply, but this is what I got with the link:

Access forbidden!
You don't have permission to access the requested object. It is either read-protected or not readable by the server.
If you think this is a server error, please contact the webmaster.
Error 403
www.saunalahti.fi
Thu Apr 14 17:15:40 2022
Apache

It IS a work computer, but I am the manager and do not have any restrictions so not sure why I cannot access.