Audi A3 Climatronic: Installation & Probleme

Translated on 07-09-2026, 0:54.

Hello!

I'm having a problem with the air conditioner; it's not working, and the compressor isn't turning on.

The air conditioning system has been recharged.

under MWB 10.3, pressure switch/high-pressure sensor, F129, 0.0.
MWB10.2 Compressor intervention required. 1.0
MWB 10.1 0.0

I've already tried replacing the fan control unit for testing, but there's no change.
The pressure switch is also new.

There are 12V at the pressure switch.
I'm getting 2.8V on the signal cable of the pressure switch at the fan control unit.

The compressor shut-off conditions are also set to 0.

If I bypass the wires for the compressor coupling, the compressor runs.
Does anyone else have any ideas?

"Thank you."

Translated on 07-09-2026, 0:56.

Please run a complete error scan.

There are only two possibilities.
- Climatronic is either not working or cannot be activated (due to a wiring fault).
- Climatronic not working (pressure switch signal).

Best regards, Rainer.

Translated on 07-09-2026, 0:56.

Hi!

Please find the scan attached.

Translated on 07-09-2026, 0:57.

How about...

Quote:

01039 - Sensor for coolant temperature indicator (G2).
30-10 - Interruption / Short circuit after positive voltage - Occasional.
00779 - Temperature sensor, outside temperature (G17)
30-00 - Interruption / Short circuit after positive

as a cause?

Best regards, Rainer.

Translated on 07-09-2026, 0:58.

I deleted it, and the errors have stopped appearing.

28-06-2011, 22:02 Subject: Audi A3 Climatronic: Installation & Probleme

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Translated on 07-09-2026, 0:58.

chriskross wrote:

I deleted it

.

Without ulterior motives? Why are there errors in it?

Translated on 07-09-2026, 0:58.

Okay, I will check it again.

But if the G17/G89 sensors are providing incorrect values, then I should be seeing an "8" in the compressor shut-off conditions.

Translated on 07-09-2026, 0:59.

What values do you have in measurement block 1, 10, and 11 of the Climatronic control unit, with the engine running and the "Auto" button previously pressed?

Best regards, Rainer.

Translated on 07-09-2026, 0:59.

Hello, the log file is attached.

Best,
Chris

dieselschrauber · Translated on 07-09-2026, 1:00.

The error was finally found; it was a burnt-out fuse that appeared to be okay upon measurement, but it had actually burned out over time.

"Thanks everyone."

Translated on 07-09-2026, 1:00.

The classic, as so often happens.

Thank you for your feedback.

29-06-2011, 16:05 Subject: Audi A3 Climatronic: Installation & Probleme

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