Climatronic and ECU

[johnlund]

Hi,

This morning I had problems with my climatronic. The display didn't illuminate as usual when I turned on the headlights and there was a delay when I pressed buttons.

I got to work turned off the lights turned off the engine then switched on the electrics only turned on the headlights and the display illuminated but the climatronic unit acts differently now. I used to be able to leave it turned on shut the electrics off leave the car then the following day return to the car and the unit would default to AUTO mode. Now it doesn't do that. I have to press the fan speed up button to get it to do anything. Sometimes it's slow when doing it.

I have also notice two other things. A hiss when I turn the system off and I have just noticed tonight when I turn the fan on there is a slight rumble and minor vibration felt in front of me when the unit is on Auto running at any temp it seem the engine is under some sort of load in AUTO. When I select ECON the vibration and rumble goes

1) Is the climatroinc controlled in anyway by the ECU

2) Where can I find the diagnostic plug for the ECU. I know in a friends Polo it's located just behind the ash tray in the front.

[tjompen1968]

The ECU does not directly control the Climatronic, it has its own controller. The connection is located between the front seats, http://dk.openobd.org/einbauorte/vw_passat_3b.jpg

or

http://dk.openobd.org/einbauorte/vw_passat_3bg.jpg

[johnlund]

Thanks for the reply any ideas on what the problem could be with the climatroinc and is the hissing sound normal.

[johnlund]

When I switch the climatronic and engine off I can hear a hissing in the rear drivers side of the engine compartment. I have an 03 Passat. Is this hissing normal. I can see what looks like two valves in the vasinity of the hissing.

[tjompen1968]

Sound like it's leaking gas?

Same on mine and to me it appears normal.

Well, there are two tubes passing from the compressor I guess, into the cabin, one with a block coating and one without, one is really cold and on my swedish car these are on the right side of the car, next to the fan-filter, is this the source of the hissing? It is on mine...

[johnlund]

Sound like it's leaking gas?

Same on mine and to me it appears normal.

Well, there are two tubes passing from the compressor I guess, into the cabin, one with a block coating and one without, one is really cold and on my swedish car these are on the right side of the car, next to the fan-filter, is this the source of the hissing? It is on mine...

Im not to sure about what the anatomy of my car is in full but yes one of the pipes is very cold where the sound is coming from. I have a cover in the way where the sound is coming from but through the holes in the cover I make out two screw on stops or bleed valves i guess.