I've just got home after being recovered from a breakdown.
For the last couple of months my heater fan has behaved erractically, at random and not normally for long periods. The display show no change when it happens, but you could hear it blowing quickly from slow to a slightly faster speed when set to Auto. No big problem I thought. I'll just wait for it to stop working and I'll get the Final Stage Resistor replaced. Also, my air conditioning pump has been a bit noisey since getting the system regassed 6 weeks ago, but works great.
Then two days ago after being nearly stationary in a traffic jam for 45 mins (probably the longest it's had to cope with) the radio volume faded and the red battery light came on, just for 3 seconds as I got to the front of the jam and drove off, and everything was back to normal.
Today after doing another 50 miles or so since that slight hickup, I get all sorts of problems. I was cruising along the motorway when suddenly the battery light came on again, the auto gearbox warning came on, and the car went into limp mode with the general warning amder ! triangle light on.
I pulled over, turned off, waited 2 mins, restarted the engine and was able to crawl until you feel it go into second gear and then it all happens again. I called for assistance. 90 mins later when they arrive we try to start the engine to get it onto the flatbed and all the lights flicker and it won't even turn over. The car is now sitting on my driveway with a completely dead battery.
Any ideas? Alternator? FSR? Bad earth/connection? Clearly it's an electrical fault, rather than a gearbox failure, which I guess is a relief. It's a 2002 E46 325i Auto. Owned for 18 months. All been good until now.