After my 1998 318i (86K miles, 4 door) sits out under the hot Texas sun (100 degree+), the air conditioning works for a couple of minutes (after I first turn the car on), and then it shuts completely off (no air, period). The heating/cooling LCD instrument panel goes dim (I can still see the temperature and the bars) and when I push any of the buttons, it doesn't do anything.
To fix the problem, I'll pull off the road and park in the shade with my hood up for about 20 minutes. Afterwards, the air conditioning works fine and will remain on for the remainder of the trip (despite driving in 100 degree+ temperatures).
I've replaced a couple of fuses, but obviously that wasn't the issue.
I live in a rural area and the closest BMW dealership is a long ways away. The import shop I take it to can't replicate the problem because they are too impatient to let it sit outside and then drive it around although I tell them the exact symptoms. They just topped off the Freon and replaced the filter and that didn't fix the problem either.
Can anyone help?
Last edited by Flaming (10/4/2010 9:47 AM)
Heat is a big problem for electronics.
Try having the car sit in a shaded area when it gets that hot again, to avoid the car from getting too hot before you drive.
When the problem occurs, it sounds like the interior gets really hot. When you sit in the shade the interior cools off, the A/C starts to work when it cools off. It will remain working the rest of the day because the interior is cooler and will stay cooler as long as you drive, so the problem doesn't occur again.
The dimming of the A/C control is a dead giveaway that the electronics are at fault.
This is a simple experiment for you to do. If you can keep the car shaded and cool, and the problem doesn't happen again then it sounds like the control module is shutting down with the excessive heat. Keeping the windows cracked open and shading the front and rear windows can help keep the heat down for this experiment.
Unfortunately you will need to go to the BMW dealer for this repair. They can also check other A/C components to make sure the rest of the electronics and electrical system are working properly.
Let us know how you make out.