Mercedes ml 280 4matic 08 plate

  mercedes/m-class/2006-2011

Hi guys, today my heaters & a.c. have stopped working out of the blue. I noticed yesterday that when I opened the car, the heaters were blowing but without the key in the ignition. Any ideas what is the issue with it? I'm not sure if it's an electrical fault as my back right hand break light stays on constantly, when the bulb is connected. I've only had the car a couple of months & still under warranty from the private garage I brought it from.

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