Whirring sound coming from battery side quarter panel

[Caosa]

Hey guys,

I'm in Aus just fyi (so RHD Z4M); lately my DSC lights and dash lights in general have been flashing on and off. I gathered it is probably the alternator voltage regulator after doing some research so I ordered a replacement.

I could still drive the car fine and after it became warm the lights would stop flashing. Hence I took it out today to run some errands however while the Dash lights were flashing I tried to put my windows down. Both would not respond after hearing the initial click. I'm assuming the window regulator was fried due to the alternator regulator so that was annoying.

Anyway, I park the car and turn it off but I hear a really loud whirring sound coming from the right hand side, back quarter panel while the car is off. I opened the boot and it sounded like it was coming from underneath the battery. I'm assuming it's the fuel pump. I had no tools to disconnect the negative terminal so I couldnt stop it and I started to notice smoke seeping out of the seal of the Driver's side (RHD) between the quarter panel.

I drove straight to the closest mechanic to take the terminal off. I unplugged the Fuel pump modules next to the battery, however when I re-connected the negative terminal, the sound continued. Pretty stumped - I left the car at the mechanic to diagnose but just wondering if anyone has experienced anything like this.

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