New owner, few questions!

[motas88]

Hi all,

Purchased a used MK7 GTD in a hurry about 2 months ago. Upgraded from an MK5 GT TDI Sport. Overall pretty pleased with it apart from a few issues.
Have some corrosion issues I spotted upon delivery, but they should be sorted under agreement with the dealer. The left rear light was letting in water and a few of the door seals have perished but all should be good thanks to a ‘you can’t bend it’ warranty. One problem that is not being sorted is air con.

I have no cold air with the air con on, in fact it’s probably warmer with it on than off and when it’s switched on it whines through the vents. Garage won’t touch it as there is signs of ‘front end damage’. Surround on the front radar is cracked and a few fins are missing from the condenser. Can’t guarantee it didn’t happen during my ownership and can’t be 100% sure air con was working when I purchased the car as was in Scotland and has barely been warm enough since.

Question is my mk5 used to ping a code when refrigerant was low, is it not the same with the Mk7? And if so is how can their condenser be damaged, leak gas and not bring up a code?

Have no issues replacing the condenser myself but reluctant to if it’s fine, as the garage just looked at the front and said no.

Apologies for the essay.

Many thanks.

Tom

 

[FJBGTD]

Yes you will get a code for low refrigerant, the system is very similar the the MK5 if you had the climate control version, however the diagnostics go into more detail. I'm not sure if a standard OBD reader with read the codes for ac, try using vcds or obdeleven and look at the live data in the Air Conditioning module, control unit 8, that should point you in the right direction.

 

[motas88]

Yes you will get a code for low refrigerant, the system is very similar the the MK5 if you had the climate control version, however the diagnostics go into more detail. I'm not sure if a standard OBD reader with read the codes for ac, try using vcds or obdeleven and look at the live data in the Air Conditioning module, control unit 8, that should point you in the right direction.

Thanks for the help. Didn’t have climate control on my MK5 but definitely gave me a code for low refrigerant. Have OBD 11 so will have a mess about with it this weekend. Bar refrigerant loss can only think of a compressor failure but the whine from the vents when it’s on makes me think it’s something else.

 

[motas88]

So no codes, refrigerant pressure seems good. Clutch kicks on and off as normal. I’m stumped. Did a reset and output test all seems functional but still no cold air. That whine from the vents seems to indicate something but can’t find anything online to help diagnose the problem. Any ideas?

 

[motas88]

So, bit more info for anybody who actually knows what they are talking about because I’m just taking educated guesses here. Haha. Checked a good few things today:

Cabin filter, ok.
All fuses ok.

Through OBD 11, rechecked the pressure which sits at 3.8 bar and then when AC switches on it spikes then starts falling back down. (Don’t know if this is normal).

Compressor load values do read out when AC switched on so assuming this is working.

Only thing that’s stumping me is the cooling fan does not switch on when AC does. The fan works as have output tested it and it has come on in stop start traffic. So guessing the AC control unit is not telling the fan to switch on. Could it be as simple as a broken wire or am I just being hopeful?
Notice from research about this that there is a connector under bonnet top O/S of rad that has been linked to this, mine does seem a bit loose. Before I could break out the multimeter heavens opened so wondering if this could be the problem.

Again thanks advance for any help received.

Tom