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Author Topic: Air Con Fans not kicking in from start  (Read 3231 times)

Offline pudding

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Re: Air Con Fans not kicking in from start
« Reply #15 on: November 15, 2019, 10:04:29 am »
My fans don't come on after start-up either, even on LO, but my A/C is fully functional.

The fans are PWM speed and temperature controlled from both the engine and A/C controllers.  I think you will find at this time of year, the fans won't just come on arbitrarily, but rather there is some ambient temp intelligence going on.   The A/C has less work to do over winter to achieve the cooling targets.


2007 ED30 | 2009 TDI 140 | 2016 BMW 330D

Offline ljc19630

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Re: Air Con Fans not kicking in from start
« Reply #16 on: November 15, 2019, 10:30:48 am »
Thanks, Kev, all a learning curve this! I'll test it out on my way up to R-Tech tomorrow morning. Thing is the other week I went to Maccydees and sat in car scoffing my grub :party:. Had engine running, AC on and it was pissing down and very damp outside. Windows started steaming up?? Turned fans up to the max, but it took at least 15 mins to clear. This was before I changed the AC Solenoid to an RKX part, and had it re-gassed. I also changed the Recirc flap motor as VCDS was showing as an intermittent fault. I'll leave the car out of garage tonight as early start and also will then be at ambient temperature, so if AC is working as it should I won't get any steaming up, as prior it was around 10 mins from a cold start for the ac to start performing as it should.

Offline pudding

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Re: Air Con Fans not kicking in from start
« Reply #17 on: November 15, 2019, 10:48:00 am »
It certainly is! The fans on VWs have been a pain in the hoop since the VR6.  It's really difficult to find on the web exactly what conditions trigger them, but over time you figure it out from observations! 

You may have fixed the demisting issues with your new parts and regas.  Yeah the demisting should be pretty quick when everything is working properly, certainly not as slow as 10-15 mins!



2007 ED30 | 2009 TDI 140 | 2016 BMW 330D