W164 ML 320 - Aircon

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Noticed that the Air was not a cold but this was an intermittent problem. Checking the system, sometimes when the AC is on and Max cold selected both sides, the AC light is on but no cold air and at the rad the main fan is not running. When it does work the Rad fan is on full and interior fan is at Max and it works really cold in under a minute.

MB dealer checked it out and there were no faults on Star even when it is in not working Mode. When it was working the Gas pressure etc. is OK and it cools and modulates when you turn up the Temps.

Back to the dealer again and they reset the heater Control panel. It worked for a few days but switching off the AC and back on it is back to not working most of the time.

In fail mode it is as if the AC is switched off.

Going back to the dealer on Tue to try a replacement control panel that has been ordered.

Anyone had a similar fault? Any idea where the Temperature sensor for the car interior is located?

 

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W164 ML310 2008 Air Con - Update

Update.

Dealer advises that they have a fault code from MB that shows an earth fault between the Compressor - earth point in dirivers foot well and the A/C control panel.

Need the car just now so it will have to back in at a later date mega manhours.

However... it does work now and again and after going over a really big bump on the road it works all the time for now.

Can anyone let me have a schematic of the wiring from the Control panel to the Compressor showing the loom break points so I can see if there is a loose plug?

 

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Still got the problem and going over a bump mostly fixes it if it is not working. Have checked the connection at the comp and on the controller and they are ok.

Checking the in between looks difficult as the carpet needs to come out.