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Discussion Starter #1 (Edited)
Hi. Finally some good weather here and found out the AC isn't working. As I have no idea when it was last serviced I got it re-gassed and pressure/vacuum tested to rule it out. All good.

Still no hot air. Checked and tested fuse F19 and the relay, swopped them with others just to be sure, they are all good.

Checked pollen filter, that was pretty dirty so took it out but no luck, cleaned it and put it back (new one ordered) no luck.

Bought a registered copy of MultiECUScan and checked codes. None.

In the climate control ecu no fault codes.

Pollution sensor (present) says 206%. With or without the filter in. According to MultiECUScan anything above 60 means open circuit or short circuit to V+ what does this mean?

Pressure in ac system is 6.7 bar.

Tested the AC compressor in the Actuator menu of the climate control ecu and completed the test but did not engage. No click and centre of pulley not moving and no cold air off course.

In the engine ECU I turned the compressor relay on and hear it clicking. But this can only be done when the engine is off.

Dispite I have it on the coldest setting and AC button on in the engine ECU it says AC request OFF. (in engine ecu parameters)

So next would be to bridge the relay and see if the compressor is happy to engage then. How do I do that?

Any other thoughts on this? What could stop the compressor from engaging?

All lights and displays works as it should. But that's not to say the control unit in the dashboard is sending the right signal. It is however successfully asking for heat and vent speed.

I'm stuck and hot so any thoughts appreciated.

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You have had the first thing done by checking gas level. What you need to do now is check the circuit out you will need circuit drawing though. The air con relay needs to see the low and high pressure switches in healthy state before it engages the compressor clutch. If LP or HP switch are not functioning then cooling will be inhibited.
Also what does you ambient temp sensor on dash read if that is faulty and reading low it will not allow air con to run.

With air con on and engine running have you checked for feed at compressor plug? Could be the system is fine but clutch is knackered.
 

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Discussion Starter #3 (Edited)
You have had the first thing done by checking gas level. What you need to do now is check the circuit out you will need circuit drawing though. The air con relay needs to see the low and high pressure switches in healthy state before it engages the compressor clutch. If LP or HP switch are not functioning then cooling will be inhibited.
Also what does you ambient temp sensor on dash read if that is faulty and reading low it will not allow air con to run.

With air con on and engine running have you checked for feed at compressor plug? Could be the system is fine but clutch is knackered.
Okay great advice. I'll see if I can find the circuit and those switches. But wouldn't faulty switches through up error codes?

Ambient temperature said 21 which was correct, interior temperature 21 too and I had set the ac on low.

Not checked if the compressor gets any feed but sound like a good idea. Doubt it though as I can't hear the relay click
 

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Chexk your high and low pressure sensor by completing the circuit bridge them with a wire and see if the pump clutch starts to work. If the gas is all good and correct then look towards the thermostat as this controls the system. Usually located close to the evaporator with a probe inserted about 1/3 of the way down the evaporator. Once you get your head around a air con system the are quite simple
 

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Discussion Starter #5
I'm still to check a few things. But a little update. The airco works now when I am on the motorway. Once on it stays on most of the time.

On local routes the compressor doesn't engage and air stays warm.



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