Why doesn't my rear defroster, air conditioner, auto light and windshield defroster not work? 2007 Z4
Asked by weaklandnc1 Dec 10, 2013 at 05:21 PM about the 2007 BMW Z4 3.0si Roadster RWD
Question type: Maintenance & Repair
I have a BMW Z4. Why doesn't my rear defroster, air conditioner, auto light and
windshield defroster not work? This morning, my car seemed to heat ok but then
when I couldn't get the windshield to clear, I started investigating. The blower for the
windshield defroster doesn't blow. There is one very low speed for everything and that
is it. You can turn the blower all the way up but it doesn't blow any more than the low
setting. The buttons for the rear window defroster doesn't light up or work, same for
the a/c button and the auto button. I have tested various fuses and all are good that
we checked.
7 Answers
Did you happen to figure out what the problem is yet? I have the exact same problem on my 2006 z4
weaklandnc1 answered 10 years ago
The battery got low so it went into transport mode. Two dealers said it wouldn't do that but it did . Cost 65.00 to reset it.at bmw.I replaced the battery with info I got from consumer reports.EverStart Maxx H6 it is a perfect fit.It has a vent on both sides and the cap for one side is on the plastic terminal cover.Walmart said they were not vents but they are.When you replace the battery don't leave it disconnected very long it could go back in transport mode The battery needs replaced even if the car is starting ok.
Awesome. Thank you for the info! Same thing happened to me, battery got low and I had to get a jump. Runs fine except the symptoms of the air and defrost not working. I had read this somewhere else, that the car could go into transport mode. I called my dealer, made an appt for Monday but they said it was not possible to drive it if it went into transport mode. So I will see if they will reset it Monday........ thanks again!
Same thing with me. I had the battery replaced on my 2007 Z4 and the AC, fan, etc. wouldn't work. Turns out it went into transport mode, Had to bring to BMW to fix. No problem driving it except for the AC.
Transport mode is DIY fixable. It involves the purchase of an OBD2 cable and the software that comes with it (EBay). The cable connects from a USB port on your computer (usually a laptop) to the the OBD port on your car on the underside of your car's dash below the steering wheel. Software is called DIS. Go thru a few steps and you can clear Transport Mode (delete it) from your car so this never happens again. In fact, the dealer who originally processed the car should have done this in advance. It's part of BMW standard procedures. The fact that this happened to your car is a fault of the dealership or whoever originated the car in the delivery process. Again, you can DIY this for less than $40 and a Saturday setting up the software on an old laptop.
A DIY how-to with screen shots: http://www.bimmerforums.com/forum/showthread.php?2173922-DIS-steps-for-deleting-Transport-Mode-%28with-screenshots%29-novice-level
Can this also cause the car to overheat I had the same issue need to replAce the battery