Today the BAS & ESP lamps came on again. The car has 673 miles since the dealer put in the brake booster (that was October 7, 2004 - I don't drive the car that much - obviously). Despite the general agreement that their diagnosis might make sense, I have had a nagging doubt. That doubt is now confirmed.

I had been driving the car on some short trips and after a short stop the BAS lamp came on then the ESP lamp. The BAS lamp came on just at the end of the start cycle. The BAS lamp remained on for a minute or so after I shut down for my next stop. When I restarted the car after two minutes or so, both lamps had cleared. I don't have the ability to read the codes. The code last time, as can be seen above, was ESP C1406. Of course, the extended warranty expired in the months that have ensued, so this is on my nickel and I would really like to fix it right.

Any ideas? I am guessing anything related to the booster, its sensors and switches is already covered. Throw a brake light switch at it? One other thought - the battery is the original, and although it seems to start the car fine, when I tested the voltage during the crank cycle (at the jump start posts in the engine compartment) it dropped to about 8 for a brief moment.