Dec 30, 2008
-   I have the EXACT same problem. This is a perfect description of the issue.
I took my car to the dealer twice for this with no resolution. At first they said it was a bad or missing washer block that they had to special order. They replace that but it made no difference.
The problem seems to occur every time I leave the office parking lot in the evening > cold engine, acceleration, left turn, slight bump/vibrations in the road. Left headlight goes off, I turn the lights off then back on and it "fixes" the problem. For me, it does not seem to reappear until the next day. But it does happen (almost) every day. If I go particularly slow on the parking exit, I see the light flicker but it does not shut off.
It's certainly electrical/mechanical, it's reproducible, but so far, not fixable. It seems that cold weather amplifies the problem. When the car is warm, it never happens!
I look forward to a resolution.
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MrDasher