A/C Compressor Non Functional - Odd Reason

mcs · #1 17th November 2016, 10:53 AM

Hi All,

Hoping someone can help me, I have been researching the reason and how to mend it but I can't quite seem to get there.

My A/C was regassed recently and has been superb until the other day when I was checking the engine fault codes. I wandered into the 008 HVAC and found a flap threw a code. I wanted to check it but I did a basic settings test and didn't do it properly (I cancelled it early as it wasn't the box I wanted)

Since then, I haven't had any cold air at all. I have performed the basic settings and the tests. I have Measured the system and the compressor doesn't seem to show any reason why it isn't working. It could actually be working I would not know. No cold air at all though.

I have tried battery disconnection and fuse removal to reset the system but it seems not to work. I have no fault codes at all and everything is working but no cold air..

Any tips?

Mike

Mechcanico Lee · #2 17th November 2016, 01:32 PM

Are we using vcds ?

go into the data blocks , look for compressor duty cycle also look for system pressure , with ac off .....big differences here with ambient temps but i reckon you should see 6/7 bar .....switch ac on and see how much higher pressure goes should be around 10/12 bar with condensor fans running

Does the climate panel have the set up button where you can turn ac onto the 'econ' settings .......make sure econ is set to off to enable compressor to run

Feel the air con pipes going up towards the bulkhead area ....one should be very cold and one will be hot with ac on .

If the pressures are good or thereabouts and pipe is cold but still no cold air sounds like blend motor door not shuting over to allow air to pass through evaporator .

mcs · #3 18th November 2016, 11:25 PM

Ok so I ran the system and did all the measuring blocks.

The system doesn't produce a cold pipe going into the car (I know which one it is and its not cold at all)

The pressure remains at best 7bar.

Is there a coding reset for the compressor? Or has it just died?

All the measuring blocks are within spec apparently.

No compressor shut off codes or fault codes. No cold air at all. It was working very well last week.

Would an error in the basic settings cause it to turn off?

Mike

mannyo · #4 19th November 2016, 06:20 AM

I attempted a basic settings on my D3 in an attempt to silence a clicking flap motor, the result for me was that the basic settings failed due to the sticky motor and I have a fault code to that effect. In addition I now have a non operational flap motor, but my AC still works fine just with the engine bay recirculation motor stuck open.

mcs · #5 19th November 2016, 11:16 AM

Ok, so I drove home tonight (mix of highway and city) with working AC.

The compressor was working normally and very cold air was coming out of the vents. It was around 19-20deg C at the time.

I plugged in the vcds and the compressor pressure was 13.2bar when working which is much better than the 7 it was this morning.

The G347 threw an error code and the N280 (because I unplugged and cleaned the pins in the compressor wiring)

Not sure if the G347 is the cause

Mike