VW Golf Mk4 2003 PD - Air Con Question ( service ) Climate Control

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Mon 23 Jun 2014 09:47
VW Golf Mk4 2003 PD - Air Con Question ( service ) Climate Control - KenC

Hello Readers, I have a question about air con servicing on my 11 year old Golf, it has the Climate Control option installed.

Although the aircon is still delivering usefull cool air its been 4 years since the last service. I recall at the last air con service the local garage mention a small filter on the dashboard could /should be changed. When I asked why I did,nt get a sensible answer so I declined. In my workshop manual it is identified as sunlight pentration filter which is fitted on the bottem left of the aircon control section.

I have already changed the pollen filter and air filter, regarding the Sunlight penetration filter can anyone tell me please 1. how often these should be changed ? 2. It looks like a diy job with a screwdriver. 3.are these filters a main dealer only part ?

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Mon 23 Jun 2014 19:10
VW Golf Mk4 2003 PD - Air Con Question ( service ) Climate Control - elekie&a/c doctor

There is a sunlight penetration photo sensor on top of the dash,and an in-car temp sensor in the climate control panel.Never seen any other filter other than the cabin/pollen filter in the plenum chamber for the air ducting system.

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Mon 23 Jun 2014 19:23
VW Golf Mk4 2003 PD - Air Con Question ( service ) Climate Control - Manatee

Well would you Adam & Eve it.

www.volkspage.net/technik/ssp/ssp/SSP_208_d2.pdf

page 13.

"The sunlight passes through a filter and

impinges upon an optical element on the photo

diode. The filter functions in much the same way

as sunglasses and protects the optical element

against UV radiation."

I would have thought that the sensor would be all of a piece with its 'lens' or filter, but maybe not...and perhaps they can lose their virtue after a dozen or so years of hard work in the sunshine.

Edited by Manatee on 23/06/2014 at 19:25

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Mon 23 Jun 2014 19:35
VW Golf Mk4 2003 PD - Air Con Question ( service ) Climate Control - elekie&a/c doctor

I take it this is an electronic "filter"as opposed to a paper element type and is not a replaceable item.Never replaced one or been asked to.

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Mon 23 Jun 2014 23:03
VW Golf Mk4 2003 PD - Air Con Question ( service ) Climate Control - Manatee

Optical filter by the sound of it. Maybe the plastic goes a bit opaque or something.

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Tue 24 Jun 2014 16:47
VW Golf Mk4 2003 PD - Air Con Question ( service ) Climate Control - KenC

Thank you all for the replies so far,for those interested partiesin formation I have disconnected the climatronic control panel withdrawn it to have a closer look at the mysterious part.Behind the small rectangular grille on the left side there is a very small fan ( about the diameter of a 10p coin) at the centre when viewed from the front thru the grille there is what appears to be some type of light sensor or light sensitive diode. ( about 3mm x 5mm).

This tiny small fan always activates when the ignition is live ( regardless of whether or not the aircon or heater is switched on) and must draw a continuous air sample into itself.

I have scoured e bay and there is no sign of it, I am making the asumption that its a part that does not need replacing and probably no call to market it.( contrary to what I had been told by a garage guy)

Edited by KenC on 24/06/2014 at 16:48

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Tue 24 Jun 2014 18:08
VW Golf Mk4 2003 PD - Air Con Question ( service ) Climate Control - Manatee

The thing behind the little grille is the "dash panel temperature sensor" and the little fan is there to draw the sample air in to the sensor as you have worked out.

The "sunlight penetration sender/photo sensor" is on top of the dash near the windscreen.

Look at page 6 of the pdf I linked to above, also page 13 for more detail on the sunlight sensor which shows the "filter".

Edited by Manatee on 24/06/2014 at 18:08

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Tue 24 Jun 2014 18:34
VW Golf Mk4 2003 PD - Air Con Question ( service ) Climate Control - elekie&a/c doctor

Looking at the evidence so far,there is nothing wrong with this car.If it ain't broke ,don't fix it.

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