Air con not working

[Bobupndown]

2013 VW Tiguan. Dual zone climate control. Had regass done but no help, still not blowing cold. VW so called 'specialist' don't really know and hinted at possible big labour bills to try to trouble shoot. I'm guessing they either don't want to do it or it's difficult. Any ac specialists in this evening?

 

[Barking Mat]

2013 VW Tiguan. Dual zone climate control. Had regass done but no help, still not blowing cold. VW so called 'specialist' don't really know and hinted at possible big labour bills to try to trouble shoot. I'm guessing they either don't want to do it or it's difficult. Any ac specialists in this evening?

Is it that warm 'chez vous'....

 

[msmbus2000]

scan the car, could be getting a wrong pressure reading and check compressor is engaging

 

[The_Yellow_Ardvark]

Sometimes the pump clutch lets go, so even through it is spinning it is not driving the pump.
Or semi driving the pump.

 

[Gragson]

If you can't pin it down on here, On the Honest John technical forum there is a really good guy on AC and electrics (AC & Elcy doc) he's helped me out no end, he posts regularly with really good advice.

 

[zx9]

I suppose it is too obvious to ask if the electric fan runs?

 

[premmington]

2013 VW Tiguan. Dual zone climate control. Had regass done but no help, still not blowing cold. VW so called 'specialist' don't really know and hinted at possible big labour bills to try to trouble shoot. I'm guessing they either don't want to do it or it's difficult. Any ac specialists in this evening?

Next step is to engage the pump with a scan tool - actuate and drive the pump with VCDS or ODIS. See if pressure rises - see if any pressure or temp sensors have failed and not reading the right feedback.

By driving it with a scan tool - you will prove the feeds and earths to spooling solenoid.

This Tiguan has no aircon clutch - it is a Clutchless Variable Displacement Compressor


This is such a common failure - I have a spare spooling solenoid at our workshop with extended leads soldered onto it - so I can use an inductive amp clamp and a scope to see if pump is working - as some feedback on diagnostics can be misleading when you have a mechanical failure in the pump.

​

We have changed a lot of pumps on these VAG engines from about 70.000miles upwards.


I have also seen - the multiplug just fall off these pumps - just pop off on their own and cause failures. Put plug back on and superglue is your new best friend.

 

[voipio]

Check for leaks in the aircon system, just in case the regas has headed for the stratosphere. The compressor oil contains a fluorescent indicator, so a recent leak should be obvious, especially with a UV lamp. It might be worth getting an aircon regas adapter with a pressure gauge, that fits on the low side port, and use that to check the pressure in the system. There's no need to buy the gas itself. Noting the comments above, if there is a decent pressure at the low side port, and the pressure reading rises by a fair amount when the engine is switched off, that would suggest that the compressor is running OK.

 

[Ross365]

Car AC systems have two valve connectors (on each of the low and high pressure sides) and you can connect a suitable dial pressure gauge (if you own one) to each and learn a huge amount about what the system is doing; no computers needed. An AC specialist might well analyse the problem in a few minutes.

If you search Google, you can find fault diagnosis tables which tell you the implications of non-standard readings on either side.

 

[droopsnoot]

I suppose it is too obvious to ask if the electric fan runs?

This was the problem on my TT, albeit with the less complex single zone system . There's a fan on top of the battery that powers the fans, and they have a habit of getting dirty connections, which makes them get warm and can damage the fuse holder. I had mine gassed last year when it wasn't cooling very well, but the person doing it noticed there was a lot of gas in it, and it didn't get any better. I then noticed the fan wasn't working, and without that there's no cold air. Swapped that fuse, and cleaned the connections, and it's fine now.

 

[Ashley Burton]

Not saying it is at fault, But pressure sensors always seemed to be common on VAG vehicles from my experience

 

[zx9]

This was the problem on my TT, albeit with the less complex single zone system . There's a fan on top of the battery that powers the fans, and they have a habit of getting dirty connections, which makes them get warm and can damage the fuse holder. I had mine gassed last year when it wasn't cooling very well, but the person doing it noticed there was a lot of gas in it, and it didn't get any better. I then noticed the fan wasn't working, and without that there's no cold air. Swapped that fuse, and cleaned the connections, and it's fine now.

I thought I had that problem on my A4 but it was the fan that needed replacing, a little bit more expensive but an easy fix.

 

[8ob]

Sod the air con, wire the switch up so it opens the sunroof, job done

Bob

 

[premmington]

Not saying it is at fault, But pressure sensors always seemed to be common on VAG vehicles from my experience

I think I have only changed one Aircon pressure sensor on a VAG group car - a 2013 Skoda Fabia.

I am contanstantly feeding Japanese cars - Hondas/Nissans/Toyotas/Lexus's pressure switches for the aircon systems (god do these cost large amounts of money from the dealers).

Not sure why they fail wholesale so much on Jap cars - but they do (along with aircon clutch control relays)....

Jap cars do hold more PAG oil Denso pumps spec huge volumes of PAG - maybe the oil floating obout the system does it? Who knows?

VAG cars are normally a hole in the front condensor or the pump itself - sometimes it can be the cold air flap motors in the heater box as well.

 

[Ross365]

Aren't the pressure sensors just like oil pressure switches? I think they need to see a minimum pressure of 25psi to close and allow the compressor to work. If they see less than 25psi they assume lack of gas and stay open. Of course, I may be thinking of the older cars which I drive; maybe it's gone hi-tech now?

 

[Revs1972]

When the aircon stopped working in a Renault Scenic years ago, mate suggested changing the cabin pollen filter and it all sorted itself out. Wonder how much an investigation at a garage that would have cost.
Sometimes its the simplest things

 

[Bobupndown]

When the aircon stopped working in a Renault Scenic years ago, mate suggested changing the cabin pollen filter and it all sorted itself out. Wonder how much an investigation at a garage that would have cost.
Sometimes its the simplest things

Already changed the pollen filter, no joy.

 

[Bobupndown]

Sod the air con, wire the switch up so it opens the sunroof, job done

Bob

If only modern cars came so equipped regularly, I much prefer a sunroof and would use them in most weather conditions. Unfortunately less and less cars offer them and where they do they are a big cost option which 1st owners seldom pick. My car purchases are almost always 2nd hand so buy what is available and in budget on condition more than spec.

 

[premmington]

If only modern cars came so equipped regularly, I much prefer a sunroof and would use them in most weather conditions. Unfortunately less and less cars offer them and where they do they are a big cost option which 1st owners seldom pick. My car purchases are almost always 2nd hand so buy what is available and in budget on condition more than spec.

I like a proper tilt and slide sunroof (big budget item on spec for a new car).

What I don't like is "glass moon roofs" on cars - that don't open! Why?

I don't like Cabriolet cars either - wifey has a few over the years - they just look like a "skip" to me with the roof folded.

 

[Bobupndown]

Have a skoda in work, full size glass panel in roof, doesn't open, looks nice, makes car too hot. Loved my Discovery 2 with 2 opening sunroofs!